Image from here.
It's no surprise that Mark Cavendish was selected for the tour team to win the green jersey. After his crash in the Tour de Suisse, I'm just surprised he's recovering so fast.
The general classification (GC) contenders for HTC-Columbia are Michael Rogers and Tony Martin. Rogers is the lead GC, but Martin is coming off a very successful Tour de Suisse. He held the yellow jersey in the beginning of the race and beat Fabian Cancellara in the final stage time trial. No one has beaten Cancellara at a time trial in 3 years until Martin did.
HTC-Columbia has a very strong team. Look for Cavendish to win the green jersey, and a top 10 finish from the GC hopefuls.
More info here.