I think it will be Brandon Roy. Brandon is the most complete player in the draft and is extremely versatile. He can realistically play SF, SG, or PG in the NBA. He will be an assest to whatever team he goes to.
Shawne Williams and Ronnie Brewer are going to be the sleepers
I think Shawne Williams is a good prospect and a worth late lottery pick. However, I don't see him as a roy candidate no matter where he will play next year. He may need a couple of years to develop.
As we know, who will be ROY depends a lot on where each prospect will go. Morrison would be a safe bet. I think Foye is also kind of a player that can contribute immediately. Bargnani has a chance, and so does even Tyrus Thomas if he gets to play in a suitable system. I still believe Gay is the most talented prospect in this years draft, and he could be one of those players who are more suited for nba than college game. If that's true, he could be the ROY too. Shelden Williams could have monster stats if he will go to Atlanta. Marcus Williams may collect loads of assists if he gets to start and play with a scorer.
I'd like to see someone like Jordan Farmar or Ronnie Brewer win ROY, but I don't think either scenario is likely. Generally, the most NBA ready player on a high lottery team wins the award (Okafor, LBJ, Brand, Paul, etc), so I'm leaning towards Morrison or Roy, like everyone else is. I'll give the edge to 'The Stache,' just because of the nickname and the fearlessness.
I think Reddick could possibly be a real candidate for a sixth man award. Maybe not this year, but a good bet for the best years of his career. Sadly, his "D" skills will be exploited unless he goes to a team with a team defense style coach..ie Utah or San Antonio or others like them.