Iirc the problem was far worse on PS3 because the service is free and doesn't have anywhere near the dedicated security and resources Live has. Should see it on PC through Steam though, it's even worse than PS3. It uses IW's crappy security, not Steam's VAC, so nearly every game you play is full of aimbots and hackers. What really sucks is if you're in a hacked game and IWnet picks it up it doesn't ban the person modding the game, it bans everyone in the game and you can't appeal Steam bans. I got permabanned on it right after I hit 70 that way and I tried for months to get Steam to lift the ban but they won't even reply to appeals.
Motorcharge from JF and Nightcrew