I agree that scouting is way better but I still don't want to 'wait and see how this plays out'. I want to trade some of these prospects and soon. Why? even with better scouting maybe half the top 10 will be really good and few after that.
I suspect that it has much less to do with scouting and much more to do with statistics. We have a much better understanding of how basic performances correlate with major league performances than we did 10+ years ago. Corey Patterson offers a good example. People noted his lack of pitch recognition when he was a minor leaguer. However, scouts and FOs "knew" that guys often improved pitch recognition with age. Except, of course, that it turns out that they don't: and the BB-rates (and K:BB ratios) that guys put up at young ages in miLB are very predictive of what they'll do as MLBers. Patterson was, in the end, just another datum there.
Vitters' main problems is that expectations are also unreasonable (timing people seem to think he's older than he is) and a few minor injuries. It's way too early to say he's anywhere near a bust, and probably the closest prospect to the major leagues.
Vitters was one of the last guys drafted for whom we were promised that his pitch recognition would improve with age. By 2008, only a few FO's still believed that: and the Cubs had one!
Vitters will always be a guess hitter. Really, his ceiling is a Jeff Franceour type that some old-schoolers love, but providing very little (or no) value to his team due to very poor OBP.