Marvel Ultimate Alliance is very fun, as is Test Drive (Psi, wait until you see the pure ignorance that is terrorwrist's painted car collection..we'll get together sometime soon).
One game that I think I'm going to be forced to buy is Viva Pinata. Despite the childish graphical look, the game itself is very dark, at least according to other's impressions. Forcing a son to **** his mother and then murdering their offspring with a shovel in order to advance in the game? Sounds good to me!
EDIT: Since Amazon has Viva for about $46 shipped, I had to get it. Plus, this commercial is rad.