I fucking loved the first 4 Call Of Duty games (especially 1 and 2). Sad to see where that franchise has gone.
Also, Mass Effect. The third one was such a huge letdown that I'll never return to that series.
I would even say that MW2 added enough to the multiplayer to make it extraordinarily awesome, but I agree, the next games have been bummers. Best after MW2 was probably BlOps 2 for me.