(Xbox) i believe it is now patched. there may be a way of doing it though. i tried to delete the patch for it and it would have worked if xbox did not have the auto-update thing when you sign into xbox live. i also tried many other ways, and i have come up with a theory that could work.

so when you are asked to update the game, you can choose whatever storage unit you want the update downloaded on. i believe that if you download the update onto a removable device to then do the glitch without the update active. unfortunately, the game will quit whenever you remove a storage device. i know it seems a bit extreme, but maybe if you get one of those Wi-Fi Hard Drives, you could download it to that and then turn the HD off, therefore disabling the update. i am unsure if this would work as i don't have a Wi-Fi HD, but if anyone who is reading this does have one, give it a try because you will never know until then.

(PS3) i am not sure if it is patched or not, but there was definitely a way of reseting your stats. have a little bit of a search through youtube and google for it, but pretty sure Treyarch patched it