Chat speak can be invaluable, as your rightly note, for conveying tone in e-mails.  It can turn what would otherwise seem mean into a friendly jab.  Three things that do annoy me.  1) the use of chat speak in lieu of a standard English expression that better captures the point or at least captures it just as well.  2) The use of chat speak as a kind of speech tick.  I have received e-mails where "lol" was used in ways that just looked like e-mail nervousness (like a person giggling inappropriately because they are stressed).  One of the benefits of e-mail is that it allows you to collect yourself and not be nervous in your communications with others.  3) I have students who seem to have lost the ability to write a formal e-mail.  E-mails to your professor aren't simply text messages done on a computer. This is especially so when you are asking for a favor that will take a substantial amount of time to fulfill. Admittedly this isn't the fault of chat speak per se, but excessive chat speak does cut down on the formality of communications, and some communications should be formal in tone.

This goes in hand with your Sabermetric Fatigue posts. It's literary elitism. And chatspeak is counterintuitive and unacceptable in the PhD review room.
Now, I don't encourage chatspeak. In fact, I'm a twitter user and I make it a point NOT to use chatspeak because it reduces the challenge of being elloquent in 140 charaters. Like Shakespeare said, brevity is the soul of wit.
But linguists, from what I have heard, accept the fact that chatspeak and its brethren are part of the evolving English lexicon. Much like the recent Oxford English Word 'unfriend', which is a complete bastardization of the English language per se, English experts accept that chatspeak is a natural evolution of the language.
Chatspeak is nothing harmful. It's the users of English adapting to typing with just thumbs.
(Somewhat off topic, but LL's two rules of no politics and no chatspeak are, for me, overly intolerant. I couldn't even comment on the fact that Barack Obama was making the first pitch at the All Star Game. The 'spirit' of the rule is to keep out political bickering, yet I was still smited with the rule on the comment that Barack Obama, our president, was throwing the first pitch. I have yet to return.)

I work with 6-12s in a K-12 school every day.
What students suck at is pure and simple email etiquette, and NOT because of their command of chatspeak. And that's no surprise because, IMO, our curriculum doesn't teach *email* writing, even if it does *letter* writing. And most students aren't smart enough to transfer *letter* writing skills to *email*. Most schools, I imagine, also don't teach things like the lack of emotional transfer on paper/electronic vs. talking.

In defense of a strict no chat speak rule:
 
It is quite reasonable for a blog to want to avoid an overabundance of chat speak in the comment section.  If you start getting too many posts like this:  OMFGBBQ FELIX is so L33T LOL he totally ROXXORED that guy LOL!.
Too much of it does turn the comment section into something a bit tasteless, and it is a legitimate interest of a blog to have some say in the style, content and tone of the comments section.  
 
How can you achieve a goal of limiting chat speak?  One option is to just use subjective appraisals of what counts as too much.  Unfortunately, people get pissed off when you use subjective appraisals like this.  So that leaves a second option, you just rule it out entirely.
I don't really have a stand on what the right option is, but I would be loathe to infer elitism since there is another more reasonable interpretation.  

The idea behind the capitalization/no-chatspeak rule is to enhance readability while forcing people to think a little more about what they're saying. We're more lax in game threads, but those aside, we pride ourselves on being a readable community. A crude one that isn't for everyone, to be sure, but a readable one. And while the occasional lol isn't bad, one needs to be strict, because allow one lol and you're on the slippery slope where you start to allow more and more, and then you turn into the average Internet community instead of a better one. The average Internet community is borderline unreadable, and we'd rather not take our chances. Anybody who has a problem with having to write in more complete sentences is someone we probably don't want hanging around anyway.
(Emoticons are permitted, for whatever that's worth.)
As for IcebreakerX's remark, I know it's strict, but consider the following hypothetical exchange:
"Hey, Obama is throwing out the first pitch.""I bet his pitch will fall short, just like everything else he's tried.""(escalation)"
Nothing tears an Internet community apart quite like political bickering, and so this is one area where we absolutely have to have a no-tolerance policy, because people love to argue politics, and if you give them an opening, they'll take advantage of it. It's rarely the first political comment in a thread that we have a problem with. It's the potential fallout. Your comment, on its own, would've been fine. But the odds of it being left alone aren't guaranteed, and we don't want to have to deal with the downside, because political arguments can be ugly.
You could make the argument that our readers are smart enough to be reasonable. Most of them are. But I'm not going to take that risk.

I'm also just not the biggest fan of reading chatspeak, and while it doesn't offend me, I've read other SBN communities and seen what can happen when you combine chatspeak with auto-updating comments. There are sites out there that will have one funny comment followed by five LMFAO's and five +1's. And maybe I'm weird, but I just find that really annoying. Reminds me too much of myself IM'ing as as teenager.
 
We may be a little strict about our rules, but on the other hand, no one worthwhile is going to be scared off by a no chatspeak/no politics/no religion policy on a baseball blog, so it's all upside.

 
I gather that if there is a reasonable objection to the AGW thesis it is not that there isn't an available mechanism (greenhouse gases) that we would expect to have the result of increased global temperatures all other things being equal, but rather that we don't know if all other things are equal.  I.e. we don't know if there aren't other compensating causal factors.  Second, I gather that the objection is that we don't really know the degree to which (no pun intended) greenhouse gases would increase global temperatures, all other things being equal, and hence we can't with any high level of certainty look at the actual changes in global temperatures and say that such and such a percent is due to greenhouse gas emissions.  
 
Anti-AGW could really be any one of the following, and it is sad that they all get lumped together, since there actually is a serious debate to be had over 3-6. The political discourse unfortunately is such that on the left you are branded a heretic if you take anything on this list seriously, and on the right, you are branded a heretic if you think that there is merit to the AGW thesis at all (which 3-6 of the following do).  
1) You think that global temperatures aren't rising (these people, I gather, are simply wrong)
2) You think that temperatures are rising, but that it's not attributable to human activity in any way.  (again, I gather that there is little disagreement amongst scientists that these people are also wrong).
3) You think that temperatures are rising, and that it is partially attributable to human activities, but that the percentage attributable to human activity might be substantially lower than we have been led to believe by Gore, for instance.
4) You think that temperature is rising, and that it is largely attributable to human activities, but that the expected effects of increased temperatures are not likely to be as dire as we have been led to believe by Gore, for instance.
5) You think that the temperature is rising, and that it is largely attributable to human activities, and that the expected effects of increased temperatures will be dire, but that stopping greenhouse gas emissions will  be very expensive, and have similarly dire consequences for the economy.  A cost benefit analysis of the situation would favor not accepting substantial limits on greenhouse gas emissions. 
6) (a variation on 5, I think) You think that the temperature is rising, and that it is largely attributable to human activities, and that the expected effects of increased temperatures will be dire, but you think it is too late to do anything meaningful about it.
 
As an added wrinkle, even if I granted that from the perspective of pure science, your analysis would be right Matt, the worry is that this is a decision under uncertainty with potentially dire consequences if we get things wrong.  If someone said to you "given our current best evidence we think there is about a 30% chance that you have cancer that will kill you in 6 months if untreated.  If treated you will have a 90% chance of survival. You have two options.  1) you could do a range of other tests that will take 5 months, after which our certainty as to whether you have the cancer will approach 90%.  If you do have the cancer, though, at that point you will almost certainly die.  2) We can treat you, hence giving you a 90% survival chance, but the treatment is very expensive, and you will end up paying us 30% percent of your income for the next 20 years."  Which would you do?  I'm not claiming that the answer to this question is obvious.  Perhaps you don't even agree that this is even (roughly) analogous to the decision we do in fact face vis a vis global climate change.
 
In any case, I'm curious whether you'd agree with this appraisal of things.

I should add that the point of thinking of this as a decision under uncertainty, is that it partially cuts through the political games.  If someone came up with a believable policy that would cut greenhouse gas emissions by 90% and cost only 10 million dollars, then everyone ought to support that policy who thinks that there is a non-negligible chance that the AGW thesis is true. (and from what I gather, everyone should believe that there is a non-negligible chance that the AGW thesis is true).  I don't know what the level of certainty or the cost should have to be for accepting any particular policy proposal.  But being in principle opposed to spending money on greenhouse gas reduction, (or conversely being in principle committed to spending whatever it takes to cut emissions) is not a tenable position.  I get the impression from certain right wing pundits that this is the stance they have taken, or at least the eye-rolling behavior every time global climate change gets mentioned indicates as much.

To say that AGW policy will "certainly" create a disaster is, I hope, supposed to be rhetorical hyperbole.  There are any of a number of policies that could be adopted, plus we don't know with "certainty" what the future of technological innovation will yield.  Perhaps with limited funding, motivated by a concern for AGW, we can stumble on carbon neutral energy sources that are even cheaper than the carbon producing alternatives.  You are stacking the deck here.  
My point was a formal one.  This IS a decision under uncertainty.  Of course, different beliefs about the percentages and costs will alter what policies you think we should adopt.  
My only point is that the 'purist" positions that say either we have to spend whatever is necessary to stop AGW or, we shouldn't spend anything on AGW motivated concerns, are irresponsible.  There will likely be promising "carbon reducing" research proposals which should be supported because they are good buys, even if one thinks, as you do, that the chance of catastrophe is very low.  Similarly there will likely be carbon reducing proposals that should be rejected because the cost is too high (outlawing driving, for instance).  The thought is that if we can at least agree on the form that the question is to take (a cost benefit analysis under uncertainty) we can cut through some of the more politically motivated chatter and get down to making a responsible decision.  (I should add that mere cost benefit analysis is just a starting point for setting policy.  There can also be questions of distributive justice, for instance, like when India claims that it is unfair for the US to restrict their economic development given that the US has already benefited from carbon intensive energy production.)

My classmates and I were all taught in 10th grade that 'correct' English is English that is appropriate for the setting.  Chatspeak in a formal letter, 'incorrect'.  Formal English in a video game chat room, also 'incorrect'.  : )
A person can run their blog however they see fit, of course.  but disallowing mild chatspeak on a sports blog / discussion room, that seems, uh, a bit haughty. 
Too many acronymns, or digits in the middle of words, makes something less readable for me.  But I also appreciate the economy of IBIWISI and other internet shorthand.  These are words that can have great utility, to both the typer and the reader.  But the economy can be lost if there are more acronymns (or too many obscure ones) than your audience can handle.  If your audience isn't teenage or young adult computer geeks, they likely won't get the meaning, or will have to waste 15 minutes of their time looking them up.
Words like LOL and emoticons perform an additional function, that of communicating emotion.  They modify statements, and their inclusion can completely change the meaning of what someone types.  IMO they are very important to almost all non-formal net dialogue, because they help fill the void created by the absence of face-to-face communication.  
WTF is an interesting one, because it seems to actually bend language in a (slightly) more civilized direction.  You communicate the obscenity without writing it.
Anyway, I see chatspeak as an evolution and a net 'plus' to lanuguage.  If a blog censors it all of it, it's their loss.

Speaking from the point of view of someone who has spent way too much time in über-nerdy forums where OMGWTFBBQ!!!11 reigns supreme... I gotta say that you and the rest of the LL crew do a fantastic job of maintaining the vibe and enjoyment of the site. I think a lot of it is due to the quality of the community itself obviously, indicated by the awesome dudes I've met at the various meetups, but still.
It's not easy to keep a huge community of clever nerds with too much time on their hands on topic. But yet, you've done it. Huzzah, I say.
The same applies, albeit on a smaller scale here at SSI (and formerly DOV). The quality of discussion that happens on both these sites is always impressive to me.

But, IMO, the job of a moderator is to moderate and not take short-cuts on the job. Limiting chat speak and politics, for me, is a cop out. If you don't want to police, you just have to find more police to do the job.
(Gizmodo is probably actually the best example of a somewhat good control system that seems to work for the most part.)
I do understand that most blogs are labors of love and volunteership, but I just don't agree with any spectrum of limiting the potential of the community. I prefer participting a community where I am trusted with some semblence of trust. I think banning political *bickering* is the point. Banning politics is just a missed target, and this is part of my policy making at the school I work at as well (for instance, I didn't ban games in our school until all other controls were out of the question).

What is the upside of allowing political discussion on a baseball blog?
 
If the biggest complaint about LL is that it's strict about its no politics/no religion/no chatspeak stance, I'd say we're doing a pretty good job.

There's no downside. I think a healthy community should have a variance. I agree with the idea of keeping a thread on topic, but I think there can be more tolerance on any OT topic or the like. I guess I'm more of a forum type of person, but eh.
But yes, you guys are doing a [really] good job.

In a perfect world, LL would be a 100% free community, and everything would work. But let's say I open up, say, a weekly political thread. People take politics seriously, and they take political disagreement seriously, and it is entirely possible, if not probable, that people would form strong opinions of other posters in that thread and respond to them accordingly in others.
 
I don't want groups of Mariner fans to start hating each other just because they voted for a different governor, you know?

But I guess I'm more on the side to try to make things happen. Probably my habit from working at a school. My goal has always been to enforce rules and things through community pressure than corporal punishments. It has worked to an extent here.
Great convo and thanks, Jeff. I appreciate you taking time to talk and all. 

is a big factor to consider, at least when debating the policing of interaction in any medium.  If the author/editor/policeman is able to directly interact with each and every commenter, then the likelihood of a stable environment goes quite high.  Jeff Sullivan used to have a smallish audience back when he was LeoneForThird (4?), but his writing style and overall readability have won him one of the sportsworld's biggest team-centered blogs.
There are simply too many people interacting to allow for 100% free engagement rules.  Once you get into his type of traffic volume, the spectrum will be completely represented on pretty much any variable, whether it's political, social, economical or even geographical.  I agree with Ice about disliking the *types* of rules that LL enforces, but I understand that they're absolutely necessary.  For example:
I used to be a poster on bloodyelbow.com, which is the premier MMA site out there.  The quality of writing, analysis and newsfeed is unmatched anywhere.  I know, because I've tried to find its equal.  They banned me because I disagree with a fundamental principle that one of the chief editors espouses, and I did so quite eloquently and effectively.  Their rules and enforcement are harsh, really harsh.  But it's because of those rules that their quality is unmatched.  They attract people (like myself) who don't get bogged down in the mindlessness which all-too-often permeates online interactions (for whatEVER reason), and who can interact intelligently and debate issues fairly even-handedly.
The other big sites out there have no such rules, and there's basically zero point in reading the threads because of the degenerative nature of the comments.  At BE you would find tons of good info and insight in the threads, often making the article itself pale in comparison to the community contributions.  Everywhere else, it's basically just the same as a newspaper blog, where you have to work a little harder than you're willing in order to amplify the original article.
So while I dislike the rules at the premier sites out there, I do understand that they serve a purpose and I also enjoy the environment that such rules (generally) help create.

Gizmodo has one of the most interesting comment policing system, and for the most part, it works well.
The idea is to have a 'core' of people who promote or demote comments. The idea, as I understand it, is to have it so as you gain more prestige on the system, you're allowed to also help out with policing by killing off trolls, useless banter, etc. It's sort of a crowdsourcing/democratization of policing comment which creates a website 'norm' through its community.
I think part of it might be technological limitations as well as non-technological limiations to an extent, but I feel that there is always a solution beyond pure banning.

I guess, but in a nutshell, Kid Nat (one of the chief editors) really wants all MMA to be co-promoted, and I (along with others) have simply demolished his arguments that it improves the sport time and time again.  He banned a guy named subo last year sometime, when I was doing my trans-pacific sailboat trip, and when I got back I didn't know what happened to him.  So I asked.
Some guys were relaying to me what happened, I said it was 'weak' the way it all went down, and Nate took the opportunity to ban me (apparently?) for saying it was weak.
Which is too bad, because I was probably one of the top ten posters there for actual technical contributions.  Oh well.  Wanna start an MMA blog with me, taro?  I've got computer programmers who could whip something up for us in about a month if I gave them the go-ahead ;)

SBNation actually performs the majority of this, or at least allows for it to be performed.
The banhammer should be used sparingly, and it should be for serious offenses or multiple repeat offenses after warnings.  For my own example, it was just a political thing.  They never issued me a single warning for anything I posted on their site, the little guy just couldn't take dissenting opinion of his position, so he took out one of his most eloquent opponents (me) with basic thuggery.
It's all good, though.  I take it as a clear compliment to my logical and communication abilities ;)  Online interactivity will continue to evolve, and the soft rules governing online interaction will become more defined as time goes on.  On the internet, the Free Market wins out.