I generally try to wait for prices to drop... but sometimes I buy on day 1 if I want to get involved in the online community right away.
1. Halo ODST
2. Halo Reach
3. CoD: MW2
4. CoD: Black Ops
5. 3DS system-- didn't get any games yet though
That is pretty much it.
Day 1 buys for 2011:
1. MW3
2. Super Mario 3DS game
Most anticipated games of 2011:
Uncharted 3,Legend of Zelda: Skyward Sword, Rocksmith
Modern Warfare 3, Super Mario 3D