That acronym will never get old.

Group A: Djokovic, Murray, Berdych, Tsonga
Group B: Federer, Ferrer, Del Potro, Tipsarevic

I think Gasquet and Almagro are the two backups.  That's important because you have a Djokovic who has his mind on his father's health and Tipsarevic who got retried with dizziness against Janowicz.  Okay, so that was probably a "I know I'm going to lose, so screw it" action, but it could be true.

Group A is clearly where the major competition is.  I'll go with Murray and Berdych there.  For Group B, I think it's Federer and Del Potro.

Semis: Del Potro d. Murray, Federer d. Berdych
Final: Del Potro d. Federer