This list WILL get longer.

the game that makes me get a new system (PC).
No really, I want to see how far they can take graphics on a computer.
Other than that, dawn of war 2 and starcraft 2 sounds like they'll be worth checking out...
I'll probably get street fighter 4 if it drops in price fast enough or if it sounds like it won't be just another fighting game(or I can just wait for the steam holiday sales again and pick it up on a whim)
I'll play fear 2 but I won't expect too much...
Saints row 2 for the PC will kill some time, hopefully.
I'd also list HL2: Episode 3...but...y'know.
But I probably will eat up whatever multiplayer game valve releases this year like I've been doing for the two years before this one.