User blog comment:FireBird-/MW3's new Survival Mode Revealed!/@comment-1647479-20110527203443/@comment-92.239.44.194-20110527220114

they had not even offically said raven software is working on the game, at the end of the mw3 trailer is just said infinty ward and sledgehammer, NOT RAVEN, i think raven is working with treyarch on their next titel, tht will make more snse coz then each main studion will have a secondary studio to help create the game.