I have now experienced several different cheats by various users. They are as follows:
Cheat called 'Earthquake mode' where there are permanent AC130 shells smashing the maps to bits
A cheat where all of the players 'fly' rather than walk. - Quite annoying.
A cheat where all players become 'infected' with some weird drug and the screen wobbles all over the place.
A cheat where a sniper shot anywhere on the screen where there was an enemy and they died instantly
A cheat where all players are bunched up in the same place, and the 'cheater' blats the **** out of them all and wins straight away
I cheat where the 'cheater' uses the G18s to shoot fire out of them. - This one was very weird.
I also got ranked up from level 69 to level 70 in Prestige 8 and scored 100,000 points today, which was a little annoying.
A cheat where the cheater locks you into the game so that you can't quit, then proceeds to launch multiple air strike (helecopters/missiles etc), and wins straight away.
An invisibility cheat, where the entire other team become invisible, and a large red square surrounds all of their opponents, making them very easy to find and kill.
That's my experience so far, and that has just been in the past week or so. It is getting stupid.
JupitersEye.