I'm selling all the way, with a bit of explanation.
Chances are, someone is willing to overpay for him.
In some leagues, he'll go #2 overall. In most leagues, he won't last past #7 or #8 because someone thinks that he'll rebound back to his 2005 numbers.
Now, he may hit 40 HR's and drive in 125+ next year. Maybe not.
But, I don't believe in gambling with 1st round picks. And there are several guys who are much safer picks than him.
I would put him at about a late 1st round/early 2nd round value. But someone picking before me will almost certainly take him before then.