So, after he was drafted, Rowell hit rookie ball pitching really well and was a super hot prospect -- I think John gave him a B+ and he looked to be maybe the best high school hitter in his class. Last year in A ball he hit a so-so 273/335/426 and it seems everyone has forgotten about him since then. He's still huge and still at third base and he's hitting 304/365/429 in hi-A in the Carolina league. What I think people forget is how freaking young he still is as his birth date is 9/10/88. That is, he'll play all of this year, his third year as a pro, as a teenager.
By comparison, Beau Mills is two years older and is hitting 233/375/388 in the same league. Cody Johnson is one month older and playing one level lower in the Sally league and is hitting 233/313/411. Michael Burgess is basically the same age and is hitting 207/292/446 in the Sally league. It's early in the season and I expect at least Mills and Burgess to bounce back, but I think it's useful to see that guys in his age group (Johnson and Burgess) aren't just struggling, but also struggling one whole level lower.
I think Rowell's age and great first half-season are masking what is a subtly exciting development curve. My guess is that he'll spend the whole season in hi-A ball, maybe showing a little more power and a little less average than he is now. Next year, though, he'll be more ready than any hitter in his age group to make the leap to AA and consolidate his skills, tools and approach, the way Dexter Fowler appears to be doing so now, except the fact that Rowell next year in AA will be a year and a half younger than Fowler is now; even if say he struggles a bit next year (which I'm not expecting) and spends all of 09 in AA and starts off in AA in '10, moves to AAA in '11, and makes it to the majors in 2012, he'd be playing all of '12 as a 23 year old, and that'd be IF it takes him '09/'10/'11 to pass through AA and AAA.