It took me a while to adjust to the system here, but I believe a lot of the lag blame has more to do with how little "auto" aim there is. Personally I wish that the snap aim was never introduced to consoles, we'd have a whole breed of lighter-thumbed console gamers on our hands, unfortunately that's not the case.
Crysis makes you earn your kills. The snap aim isn't like the FPS nanny everyone is used to, I've watched kill cams where I've been absolutely POSITIVE I was painting someone's head with my M60, only to see the bullets whizzing a nice tight outline around their head.
Shots to the body are FAR less effective than shots to the head. (More so than in most games.)
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I am not debunking anyone's claims here, merely pointing out my opinion on the matter.
Give them some time to fix things. Remember, this was recently brought to the console.