You cannot compare BF and MW
If you know DICE also created MOH which is imo compareable to MW3 since the small maps, close combat etc.
BF may also been a shooter in the modern days, the multiplayer gameplay is just a huge difference.
E.G.
The map sizes
The Class choices
The gameplay
The ammount of players
etc.
The games haven't got much in common, except that it's a shooter.
The only thing you can compare are the graphics and the singleplayer story etc.
Also Robert noted that bf will be a great game. they aren't even competing since they both know both developers know that the audience likes a game because of the preferences of both, and some will buy both. Saying that game is better is just an opinion, because the gameplay is so different.