MW.

     Both great games, and still play em both (The MWs other than 3, ofcourse). I just dont like how in Black Ops everything looks more tall and slim. Especially the weapons. Then again, theres only 1 Black Ops. Ill probably be used it after the 2nd and maybe 3rd ones come out, though.

MW2 was amazing as far as connectivity was concerned.  Posted over 35 days of playtime on that one and still pop it in from time to time to remind myself of 2 things... the game plays amazingly from a connectivity point of view but crap like noob tubes and commando really hurt the gameplay.

I got rid of Black Ops after about a week.  Just didn't feel right, took so many shots to kill people, the look was almost cartoonish compared to MW2 or MW3.

MW3... had I not bought the hardened edition w/Elite I probably would have dumped this one after a week or so as well due to the lag comp/host disadvantage BS and just been completely done with the COD series.  So many gameplay improvements (no Commando, no Danger Close, noob tubing nerfed big time, etc., etc.) but just piss poor network performance that STILL isn't fixed almost 9 months into the game's life which is simply astonishing.

If you could take the network performance of MW2 and pair it with the gameplay improvements of MW3 it would be one of the best FPS of all time.