As far as BF vs COD games go, they're both awesome in terms of overall fun. COD is excellent in terms of crazy shit talking in the lobbies, having a good laugh talking with random people on your team and the super crisp combat. BF3 is much more team oriented and is much more methodical. It just seems like it's designed for a more mature audience.
I will say, however, that COD could never provide me with the adrenaline rush moments that a game of Rush in BF constantly does. BF also provides you with pure hilarity when you just completely outsmart an enemy team with your squad by giving you almost infinite freedom on the way you approach an objective on any given (huge) map.
Both games have their frustrations with campers, BF also has the completely unbalanced helicopters piloted by skilled individuals but that's neither here nor there.
Personally, I'm choosing BF over COD this year, unless the beta manages to somehow disappoint me completely. Hopefully I'll have a chance to get on tonight. /sigh
"That's the reason my FFL team name is TrentGreenLeadBlock. When you see this mother****er coming around the corner on a block, put your children to bed and batten down the hatch on your girl's snatch, because the same power that destroys defenders can scar the minds of the youth and simultaneously impregnate any woman within sight, live or on television."