Originally Posted by pbass

Thanks for the advice folks. I should have mentioned I DID in fact take him to a couple shops, and he sat on the Specialized, and took a good test ride on the Trek. Watching him ride the Trek, it looked to fit him just right, maybe a tad big, and he LOVED it. Of course, as I mention he's coming off something that's definitely too small, so maybe my perception is off. Both the LBS people who thought it looked like a good fit with some room for growth.
It's a tough one--I can see how he'd outgrow it maybe sooner than I expect, but as you say, I want him to have something he loves to ride NOW, since his current bike is far from inspiring.
The shop that sells the Trek has a trade-up program for kids too which might be a consideration. I could buy the cheaper(than the specialized) Trek now, get perhaps a couple years out of it, and then trade up.