The thing i can't stand about treyarch COD's in general is that they always have one overpowered fag weapon that ruins the game.. In WAW it was the MP-40, In BO it was the Famas.. Where as in MW everything is overpowered so you have options. However i got to say WAW was better then BO IMO. I played BO the other night so i can remember why i hated this game so much and it didin't take long to remember. Get on mp right now on that game and i guarantee 90% of players are using the famas. Not only that but the fundementals in this game are terrible. Hit detection is more off then any COD i've ever played and it still lags after over a year of being released?
As far as MW goes COD4 was near flawless the only knock on it is now it's an unplayable piece of garbage thats been gang raped by hackers! MW3 would be perfect with MW2's maps! MW2 was dope except they over did it with cammando knifing and oma noob tubing. I think the maps in MW2 were the best in the franchise though, good mix.. There are really no fundamental problems with the game play in MW3 but the maps are terrible!
Comparing the last 5 COD's i have to say BO was the worst IMO. I just can't overlook the gameplay mechanics not working like they are supposed to...