Winner: Novak Djokovic
Even though he's ranked #2 in the world, the draw is set up very well for him. Without Nadal, Djokovic won't face anybody of great concern until the final. I see him making the final easily. I believe he will face Roger Federer and defeat him as he has done the past two years in the semifinals. Granted, Djokovic hasn't played his greatest tennis since the French Open, but he won the title in Toronto and reached the final in Cincinnati. Playing best of 5 sets favors him since Federer has a tougher draw and is older. While he may not be the better player, I believe Djokovic can win this tournament.
Finals Matchup: Djokovic vs. Federer
I think Federer will have the power to beat Andy Murray in the semifinals. While Murray is on a bit of a high after reaching his first Wimbledon final and winning the Olympic gold over Federer, I still feel Federer is too much for Murray, especially on the hard courts. Murray is also coming off a minor knee injury, so we don't know how that will play in.
Surprise Player: John Isner
My big prediction is that American John Isner will reach the semifinals. This is a bit of an odd year for him. With Nadal out, David Ferrer is the #4 seed and the highest ranked player in that part of the draw. While Ferrer has reached the semifinals before, he lost last year to Andy Roddick in 4 sets. He doesn't have as consistent a game on the hard courts. Evidenced by losing in the 1st round at Cincinnati. This is a big opportunity for John Isner. He just won the Winston Salem Open over Berdych. He made the quarterfinals last year at the US Open and I believe he will advance farther this year. He's set up for a quarterfinals matchup against David Ferrer and assuming his game is on, I predict he will beat Ferrer.
Sleeper: Janko Tipsarevic
Again, another guy who benefits from Nadal not being in the draw. The Ferrer section is wide open. When Tipsarevic is on, he can beat top players like Ferrer and Isner. He could make it to the semifinals if all is perfect. He's someone who could lose anywhere from the 4th round to the semifinals. He has the game, he just has to be consistent.
Early Exit Prediction: Andy Roddick
Maybe not much of a surpise, but as the 22nd ranked player in the world, you would expect much more from him. He has played poorly in the Grand Slams this season and is in danger of not making the quarterfinals, which he has done so consistently in at least one major a year since his career began in 2001. He could easily lose in the 1st or 2nd round. Part of the problem is fitness. He's at that point in his career where playing best of 5 sets is difficult and hard to rebound from. Who knows, he could also be nearing the end of his career as well.