I just found this Crysis awesome mod on youtube. Look at the camera movements especially at 56 seconds when he kills the guy in the tower.
Personally I love this, makes you feel right into the action.
Would you want it in the next CoD? Maybe as an option, if you don't like shaky realism you could turn it off.
This, plus 3D, would make it quite a game and refresh the CoD franchise which is becoming pretty stagnant.