Just bought BFBC2 on xbox, .. It's a far better choice then BO imo.
BECAUSE:
-Maps are bigger
-Campers aren't really a problem, since most of the time you will spot them and unlike in BO there are more roads that lead to killing him (even taking down his entire house and waiting for him at the nearest exit..

)
-Spawning system is great (if you don't mention human error's in your squad which get you killed in less then 3 seconds ..)
-Shitload of gun, including tank mines and all, RPG FOR LIFE!
-No prestiges and alot of work for 1 level up (when you enter level 20-30 or something near that you need to game quiet a while to level up even if you become first every round)
-Free map packs!
-No killstreak rewards .. HELL YES! Hated those things

-No last stand or stupid abillity's like Martyrdom..
-Snipers are realistic and don't aim like you sneeze/fart everytime you scope in.. + gravity on the bullets which makes it more of a challenge to shoot a camper on long range f.ex.
-Squads.. makes it great to play with friends online. You even get more points if you work as a team

-Not very buggy (except for the random knife bug that still happens from time to time
-Verhicles! .. (no silly RC cars C= )
-C4! Taking down a house or blowing shit up is awesome!
-You can't prone, makes sniping less overpowered in bigger maps.
Last but not least:
-NO floating apple glitch
Don't get me wrong, I also play a little MW2 on my xbox (because one of my friends still hasen't bought BFBC2

) and COD 4 on my PC here. Which I enjoy aswell, but BF just owns cod
