I'm new to Crysis 2 , but not to the FPS MP.
Yes other games do have cheaters around, but they can only do client side tweaks (wallhax + aim-bots) as long they are not the admins. Good thing is: they're dead when the server "thinks" they are. No matter what they do in game on their side.
But here in crysis 2, I've noticed guys having super-speed, no energy drain, no bullet spread, impervious armor, and god modes; along with the traditional client side tweaks.
Either the crysis servers are so weak that they are easily fooled, or there is some serious flaw in whole server - client sync of the game itself. Simply, no server-checks on player properties.
Its a great game but with very poor design. Waste of money.
:(