Huge Ackley fan.  Specifically went to see him play against the Mudcats, and he's as good as advertised.
That said ... my initial response to the idea of rushing Ackley up this year is ... "So, why again did we decide to make him play second base?"
While SSI wasn't among those that went apoplectic back in March when the whole Figg/Lop flip-flop was executed -- there was at least acknowledgement that different defensive positions have different subtleties and that while great athetes can often transition more quickly (and SEEMINGLY effortlessly) than us mere mortals realize - it doesn't mean that work and effort and TIME aren't required.
I fully expect to see Ackley in September, when it won't be costing him PT.
But, going to the trouble of taking Ackley, who played CF and 1B in college, and teaching him to play second base for a couple of months to then shove him back into either the OF or 1B --- well, that just makes your organization look stupid.  And, for better or worse, organizations are REAL hesitant to do things that make themselves look stupid, (when they can avoid it).
In September, (if out of the race), Ackley would probably spell Lopez (if he's still around) at second, and give Lopez some time at DH ... or maybe a slosh with an off day for Figgy perhaps.  If still in the hunt, Ackley becomes a potential pinch-hitter against right-hand pitching,
I get that you're just noodling.  But, bringing up Ackley before September *HAS* to come with some acknowledgement of what his DEFENSIVE role is intended to be.  And whatever that role, that has ramifications for those other players on the roster.  Suggesting bringing up the bonus baby who has been playing second for 2 months - when your current second baseman (for only two months) has just caught fire ... I'm having trouble computing the number of negative ramifications.
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As for Pineda.  Yes, he's having a great year in West Tenn.  So are about 1/2 dozen other DJaxx.  I get the attraction of the 4.50 K/BB.  But, then again, Chad Cordero currently has a 5.50 K/BB in AAA. 
My belief is that you've gotta be REAL careful in regards to hopscotch farm moves.  If you REALLY believe in Pineda, you've GOT to consider the option years equations for getting the most out of the investment.  (The "easy" hopscotch jumps are when the AA guy is called up for the 1 emergency start, instead of the AAA phenom, because you KNOW you're gonna send the AA back down immediately - and don't think he actually has a real shot at sticking).
By all means, move Pineda up to Tacoma, and see if he can out-perform what Olson did in AAA.  You learn more - and avoid a lot of potential pitfalls with "violent" organizational restructuring.
With Olson and White just called up - (and K-Tex claimed off waivers), you've got an open spot in AAA ... so, by all means, move Pineda up ... to Tacoma.  But, the organization is SUPPOSED to have a developmental machine.  It would be a pleasant change from the Bavasi era to actually USE that developmental machinery rather than simply shove talent up with ferocity (and failure).
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Oddly, I am reminded of a scene out of "Chariots of Fire" when the academics bring in Abrams to chide him for hiring a professional coach.  He fights back, (and I believe justly) that these people wish their athletes to achieve "with the apparent effortlessness of gods". 
I personally believe that many of the negative issues we have today in regards to athletics is a result of this unfortunate reality.  WORKING to become great seems to be valued less readily than simply showing up already great.  The 'naturally' gifted athlete gets all kinds of special treatment from day one - and LEARNS that he is supposed to be treated as special. 
So, I for one, am philisophically against rapid (and too often rash) decisions about players based on a month long streak (or slump).  I believe in rewards and incentives.
Has Pineda "earned" a trip to the majors?  No. 
Has he "earned" a promotion to Tacoma?  That's a much easier (and more reasonable) position. 

Gordon Beckham had 59 games in the minors before his callup to the Chi Sox last year.  He's struggling this year, but last year posted a 108 OPS+...not exactly chump change.  And it's not like his numbers in the minors were mind-blowing.  His AA stint was good but not great, and he had like 30 ABs in AAA before the callup.
Calling up Ackley to replace Kotchman at 1B isn't a stretch - he's played 1B for years.  We can always shift him over later, but that would give him a chance to get some ML at-bats under his belt.
I don't have a need to "rush" him, but he's solved AA.  A move up to a higher league is coming this year, the only question is which one - and when.
As for Hensley...he's the Pineiro of our new Big Three minor league pitching prospects.  Pineiro was on the same minor league squad as Ryan Anderson and Gil Meche.  He was the afterthought who was also doing well.  Nice kid.  Not a front-liner.
But his big-league career has been at least the equal of Meche's and far greater than Anderson's.
Hensley's got good makeup and a good arm.  There's nothing wrong with being a quality #4 arm for pennies on the dollar.  Pineda's had forearm troubles, Robles has control issues. Don't count Stephen out. 
He's another shot at a quality arm to help back Felix in our next pennant chase.
~G

Kobe started a grand total of 7 games his first TWO seasons (combined).
The memory is a tricky thing -- forgetting things like Kobe averaging 7.6 points his first season. 
Is it possible for a college grad to step right into the majors and hit?  Yes.  Bob Horner did so in 1978 at age 20 ... posting an .852 OPS as a rookie.
Ackley, at the moment, is posting a .751 OPS, in AA, and has a single HR in over 200 PAs.  He's had a good couple of weeks.  That's great.  That don't mean he's ready for ANYTHING.
I think what amazes me the most about the recent push for bringing up AA guys to the big club is that I routinely see the arguments of why picking up National League talent is a bad idea, because the talent level in the NL is *SO* low, that it is ridiculous to think hitters or pitchers moving to the AL are going to continue producing at their NL levels. 
Am I supposed to believe, moving from the NL to AL is going to snap off 10% of production for almost everyone -- but I'm supposed to expect stellar performance (or even improvement) in the AL from guys coming from the Southern League?!?
Most are petrified of Olson's return.  But, he was doing in AAA very nearly the same thing Pineda is doing in AA.
Then again, Wlad posted an .871 OPS in AAA at age 22.  Why didn't HE fix the offensive woes of the team when called up?
The West Tennesse *TEAM* currently has a .780 OPS (so Ackley is only 30 points BELOW what the rest of the DJaxx team is doing.)  Should the entire team, (or at least everyone batting BETTER than Ackley be called up), and the current Mariners disbanded?
I saw B.J. Upton in his last season in AAA.  I sang the national anthem at David Price's last AAA game.  I saw Ackley play in Zebulon just last week.  Ackley is *NOT EVEN CLOSE* to being ready for the majors just yet.  He IS seeing the ball very well at the moment.  He's got a great eye, and a solid swing.  There is a REASON he has only one HR this season.  There is a REASON why he only has a .750 OPS on the season.  The REASON is that he is *NOT* (yet) attacking the ball.  He is simply waiting for good pitches and making 'decent' contact. 
IMO, at this instant, Pegeuro would be a far better callup than Ackley.
Ackley's ISO at the moment is 112.  Rob Johnson currently has a 119 ISO against Major League pitching,
Of course, I could be wrong.  But, based on what he's shown so far, if he were to come up tomorrow, the most likely outcome would be putting a line similar to Chone during April and May -- a .200/.300/.300 (ish) line. 
Now, if you've cashed out on the Ms having a shot at the playoffs in 2010 -- and just want Ackley to be taught by your Major league coaches, while facing major league pitching - perhaps there is an argument to be made.  But, I still wouldn't get why you'd jump him over Mangini (hitting .983 at Tacoma) or Halman (.855 at Tacoma).  *HALMAN* was the uber-talented kid 12 and a half seconds ago, wasn't he?  How come posting an ISO of 300 in Tacoma doesn't merit a promotion for either of those guys?
I mean - the club starts Ackley in AA -- which by itself is considered an "aggressive" development schedule - (and mandated by contract). 
Griffey got 130 games in the minors and AROD 170.  And BOTH of them were pounding out .900+ OPS scores from day one.  Ackley has 48 games in AA, posting a .751 OPS. 
In HIS first 200 PAs at AA, Jason Heyward posted a 1057 OPS.
Let Ackley raise his AA OPS over 1000 and we can talk.  Until then, the concept of bringing up Ackley before September is, for me, a non-starter idea with a multitude of negative side effects and a near zero chance of doing anything good for either Seattle or Ackley.

Say what?
He's had a nice couple of weeks.  While a 1258 OPS over 10 games is nice ... the fact that it comes with ZERO homers and is driven largely by a .444 average tells me (along with the fact I got to see him last Friday), the he hasn't "solved" anything.  He's SEEING the ball exceptionally well.  But, a .444 average and a 20% walk rate do NOT mean he's solved anything.  Over his last 7 games, Jose Lopez has a 1219 OPS.  Over the last 14, he has a 1073 OPS.  Has Jose Lopez "solved" the major leagues?  (And Lopez has a 4:4 eye ratio during the past 14 days, too.)
Because that is 100% the exact same argument. 
 

The only reason Ackley has pedistrain #'s is from his horrible start.  Which is attributed to a few things........2nd base full time and wood bats full time.  After 1 month working out the kinks he is playing great.  IMO you can just erase the 1st month because I don't think it means anything, now May means a whole lt more.  What are his #'s in May again?

Ackley started in AA with a good eye and couldn't make the right contact.
I still don't think he's making quite the right contact, but his eye has gone through the roof.  I agree with you that I want to see more power from him.  That I WANT him making full contact with every swing and not skittering balls into the hole for lots of singles.
But that's not the league getting the better of him.  That's not getting fooled by breaking balls.
He IS seeing the ball exceptionally well.  He always has, but it's ridiculous right now.  If you want to see some HRs before promoting him, that's your call.  But if you're not there watching, how would you know if it was a wind-aided blast that's making you feel better, or if he's getting robbed at the wall on a pitch he crushed and you're not giving him credit for tagging the ball?
Like you said, you saw him.  What did you think?  I think the kid has a stroke that IMO needs some gentle tweaking to get him to stop burning worms and start doing serious doubles and HR damage.
I don't know if the batting coach for our AA team is the guy to do it.  Or AAA.  If our AA coach is the best one to take care of that, by all means leave him there.
But at this point the league is not giving Ackley any trouble.  Ackley's low power is a product of his swing, not their overmatching him.  So put him wherever you can give him the best instruction, because he's not flailing at curves and behind on FBs - his brain can already process what the league is throwing at him. 
I wanted to see Ackley struggle, and he did.  I wanted to see how he would handle it - he did perfectly. No stress, no wavering of the batting eye, he just rode it out and trusted that his hands would start doing what he told them to do soon enough.
I stand by the statement - he's solved AA.  He hasn't got his swing perfected.  Worry about that now, and not about whether a 95 MPH pitch thrown by a good prospect is a problem for him.
AA is now his personal rehab stint, and with his apparent disdain for swinging at any junk in the last couple of weeks (going on 6, but especially in the last 2) and holding out for only the drivable pitches, he seems to be thinking the same thing.  Make better, more consistent contact and get promoted.
It'll happen soon.
~G

...you've got Chone Figgins at 2B or 3B, Triunfel at 3B, Franklin at SS, Poythress and Carp at first, Ackley doesn't have an infield position...we should be prepping him to be as multi-position flexibile as Figgins so we can get him into every game without worrying about having to make trades to dump guys like Lopez and Figgins. Make sure he can field in LF, 2B, 1B, RF..wherever we need him. So we made him learn 2B...that's a tool he's got in his pocket forever...that's GOOD...even if he's behind Figgins on the 2B depth chart.

The only question is whether you let Pineda throw for a month in AAA to make yourself comfortable that his arm troubles are under control or whether you call him all the way up right away and start his service clock.

The Pineda situation has a number of differences.  (While I still have the same basic foundation principle of don't leap frog AAA except in RARE cases, many variables are different).
With Ackley:  He's playing 2B.  The club doesn't need a 2B.  While he's walking up a storm, he's not doing anything else (yet) that is remotely possible to sustain.  (He's hitting .444 during his spree, and walking .  Any takers on him hitting .444 in Safeco?).  The club already has a 1B in the pipeline, at a higher level, who has ALREADY added the power that has been conspicuously absent from the 1B slot - Carp. 
The club HAS a problem at Pineda's position (pitcher - bullpen, instead of starter - but SPs getting RP experience early is standard fare).
Pineda is at least dominating AA for 2 months, instead of 2 weeks.
The club, however, just dumped two of the underperformers, creating a vaccuum in AAA, which is therefore the much more logical spot to move Pineda in the immediate future. 
What I REALLY want to know, however - is whether the push to rush Pineda and Ackley to the majors pronto as response to the 3-game win-streak or the being 6 games back in the West two months into the season?
Actually - I'm pretty sure the push for Ackley is really just an extension of the urge to dump Kotchman.  Hey - finding a way to usher Kotchman out, I'm fine with.  He had his shot and blew it.  What I *DON'T* get (at all) is the the #1 complaint about Kotch from day one was the utter and complete lack of power -- and Ackley, while absolutely on fire, STILL hasn't shown as much power as Kotchman.
From my perspective, the IDEA of Ackley taking over at first or in LF is blantantly and indefensively hypocritical when being suggested by many of the same people who were howling over the choice of Kotchman at 1B specifically due to his lack of power. 
I've SEEN Ackley.  He is not pounding 350 foot shots off the wall in the gap.  He's hitting 200 foot liners for solid singles, which occasionally happen to be in the gap or pulled down the line.  Against AA hitting - he's hitting with about 75% of the power the Kotchman was showing in April.  Does he have a great eye?  Absolutely.  But Youklis walked 73 times in his first 276 PAs, (64 games) - literally walking more than once per game.  Ackley has a solid eye ratio, and good walk rate and is currently bringing absolutely nothing else to the table.
Now, if somebody will explain to me how the current club has so much power that it can afford to bring a guy in to provide even LESS than Kotchman ... (oh, never mind).

Doc wasn't up in arms about Kotchman being a bad choice for first ONLY because he lacked power.  He was up in arms because...between the power drain and the relatively pedestrian OBP and the GIDPs and the basepath clogging and the ease teams would find defending against his grounders...he was going to be a bad overall hitter.  He obviously does not think Ackley would be worse at the plate than Kotchman.  I don't think that either.  Maybe for a month he would.  But I think Ackley would easily out-produce Kotchman by July if called up today...he'd do it by getting on base at a .370 clip, stealing some bags, staying out of the DP, covering the plate better, playing smallball better etc.  He might not have as much pop as Kotchman, but he's quite clearly the more talented hitter.

Tough call.
I would do it, but only because I'm in the minority that thinks Pineda's arm won't stay helathy in the rotation.
If you want to work him as a starter then AAA is probably more sensible.
If you're going to convert him to relief for good then I can't think of any reason to dely him.