Star Wars: Knights of the Old Republic
Half-Life (Yeah, I'm a little late to the party, what of it?)
Bayonetta
Bioshock 2
Call of Duty: Modern Warfare 2
Top one is the most recent - sadly, with all I've got going on, I've only managed to fully play through one of those (MW2), I've made minimal progress on Bayonetta and Half-Life, and I haven't even started Bioshock 2 or KotOR. But hey, spring semester is almost over (then an amazing 2 week break until summer semester), so I've got plenty to do once that time comes.
As for my next purchases, likely:
Battlefield: Bad Company 2 (my friend has been nagging me to get that one for a while)
God of War 3
Heavy Rain
Fallout: New Vegas