Call of Duty: World At War. I had a lot of fun playing it. Not like Mw2... Also, Metal Gear Solid 4. Also lots of fun and got a 10 from IGN. Oh, and also Final Fantasy XIII which is very underrated. It has a good story and awesome cutscenes.
So much MW2 (what do you expect, casual gamers will be casual gamers....).
Anyways, games I've loved:
-Ace Combat 04 -Ace Combat X -Battlefield 2 -Rise of Nations -Call of Duty 4
All very critically acclaimed and gamer acclaimed games (unlike MW2 which is critically acclaimed, casual gamer acclaimed, and hated by any real FPS player).