I love the game. Just hate the Infinity Ward server.
MW2 I had a little lag, not too frustrating. Only problem was all of the mics sounded... distorted.
Black Ops I had no lag, and the mics sounded crystal clear.
MW3 I HAD horrible lag, until I turned off the theater recording. The lag is a bit better now, but it still gets annoying at times. The mics are distorted a bit here too. :(