it's has a very blockbustery SP and fun & addictive MP
I know BF3 has graphics (for which I don't have the PC), bigger maps, vehicles and stuff, but both BF BC2 and BF3 beta seemed more boring and less fun to me then CoD MP .. you spawn somewhere and spend a whole lot of time getting to where the action is
also, it (BF) shines mostly in team-play, but I play solo with randoms, where the hell am I gonna get a tight team ? Join a guild ? ^^
CoD is
perfect for fast firefight'y lone wolf run-and-gun fun, which is exactly what I want from MP in a shooter
that said, I'd drop both BF and CoD in a heartbeat for ~UT4 or UT2012 .. you get the idea