it wasn't one of your listed ones, but i like battlefield bad company for multiplayer. it is class-based and objective oriented. two teams: one attacking two objectives at a time and one defending. there is no deathmatch, just the main gold rush mode (and conquest if you liked that from older BF). it can be repetitive, but games are different because of the people you are playing with, and destructible environments, which makes a surprising difference. bonus: cheaper than the two games you mentioned.
+1 to this--it's too bad that COD4 killed the hype on this. It's a really cool game. Sorta like COD with lots of vehicles to use.