I have been playing both Black Ops 1 and 2 along with MW2 and MW3 and also BF3 and out off all of them I would say it all depends on how you play your FPS games.
! I DID ALL THESE BY MY GAMING OPINION NOT FAVORITE !
*In order of release
Modern Warfare 2
Realness : 7
Campaign : 8.5 ( Favorite out of all the COD series )
Multiplayer : 8
Guns : 7.5
Maps : 8
Overall : 8.5
Black Ops
Realness :6
Campaign : 7.5
Multiplayer : 7
Guns : 8 ( Liked how you could choose a ridicule for your optics )
Maps : 7.5
Overall : 8
Modern Warfare 3
Realness : 6
Campaign : 7
Multiplayer : 7
Guns : 7
Maps : 7
Overall : 7
Battlefield 3
Realness : 9
Campaign : 8
Multiplayer : 9.5 ( Never seen a Multiplayer like it )
Guns : 8
Maps : 8.5
Overall : 9.5
Black Ops 2
Realness : 7
Campaign : 8 ( Really liked how you could choose a load out for the campaign )
I never played BF3 but I've seen people play. So I can't say anything about it.
MW2 would have been the best if they fixed the connection.
Black Ops was fun but too many campers -_-;
MW3 spawns sucked booty
BO2 has its ups and down :x
Its an okay game. I could never really get into it. But everyone has their own opinions on things. I do however like the fact that kill streaks carry over.
i'll take MW3 over BO & BO2 any day. Battlefield may not have campers but the campers sit in vehicles 24/7 instead of corners. the only thing i liked about battlefield was the destructive environment & medic options. either way it goes. I'll stick to MW3 any day.