I've been playing Black ops for almost two weeks on my family's 360 and have had no issues. When the game was launched my family's 360 had no serious problems. On launch I played my ps3 version and the game is almost unplayable. Chop and lag. It's not the connection as both systems are using the same home connection. The game is noticeably more colorful and vivid on the ps3 but all that is erased by the crappy constant lag.
It's weird man, ill play 360 and it runs smooth as butter. Fire up the ps3, on same connection, same tv, its choppy as help. I literally see people float across screen and fire rate is affected. Zombies is no problem only multiplayer.
Choppy as help? I haven't heard of any issues yet. Although, I'm not getting it on my console so meh. Not even sure if I want it or not on my pc. Guess I'll wait to see if it's part of Steam's holiday season sales. Block buster games usually are.