Right, in the last week a guy found out how to hack the game save. A bit of code and such and then pout the game save on a memory tick. Then all you have to do is paste it onto your PS3 and overwrite a save file.
Now about 10% of people have it and although you cant shoot when your flying you cant get killed either. This leads to people flying to the other side of the map turning the mode off then starting behind the enemy. Or on Bog people going undernearth the ground and shooting up so they cant be seen.
I would go as far to say as almost half of the people in Hardcore Search and Destroy use this "hack" They basically fly from spawn onto a roof where they can see both bomb areas and then turn the hack off and snipe down when people are going to plant the bomb.
It is easy to enable aswell, start options circle circle then it is enabled and the same thing to disable it. Jboy is doing a count of people in the matches he plays doing it and he is already well on the way to 100.