I've been putting this off for a while now, I'll try and be as brief as possible.
Green - Mark Cavendish will win a few stages, but I don't think he has what it takes to get over the mountains as strong as Thor or Zabel, Robbie Hunter will also put in a strong showing. I think he will start off in the lead and fade back in the standings. McEwen will win a stage in the opening weeks but then complain the rest of the way thru that his team isn't helping him out. But if I chose one, I'm going with Thor Hushovd.
Polka Dot Jersey - I'm going with Soler again. If not him then I don't who. I don't think anyone can rival him if he decides to go for the climbers jersey.
Young rider. One of the Schleck brothers from CSC will take the win for that one, followed by the other, this will be at the cost of Sastre's GC standings.
For the Overall, I am going to go with Cadel Evans 1st, Valverde 2nd, and Sastre 3rd. Menchov in the top 5. There may be one fluke who falls into the middle there.
Finally, for individual stages, I expect David Millar to finally win on a long escape.
Too bad Astana wasn't there this year, I really think that Levi and Contador would have made things exciting. I don't think Contador would have been able to win again, but would have been someone to watch.
Evans riding with Popovytch will be a strong force. I don't think anyone can beat. My opinion on last years tour is that Evans deserved to win and got shafted by Rasmussen, had Rasmussen not been in the race, Contador wouldn't have made up the 23 seconds he did in the mountain stages when the two of them took off the front dropping Evans behind. Two pronged reasoning, first, without Rasmussen, Contador wouldn't have had someone to work with and built time, and second Evans killed himself a few days trying to limit losses, a risk which probably cost him more time than if he had just gone steady.
Without Rasmussen my money was on Levi or Evans, and Contador would have just been an afterthought. Sure Contador just won the Giro, but the Giro and the Tour are two very different beast.