I still prefer COD4's maps but MW2's were great as well (mostly). Also the guy that said Terminal was bad for flanking must have been doing something terribly wrong, because I found it easy running around with the MP5k.
I think a large part of the "map design issues" people see now are due in part to the lack of Stopping Power.
I'll agree that MW3 and BO2 maps weren't great and that I think MW2 had the best overall selection, but I also think my opinion is skewed due to having SP at my disposal. It made literally ANY gun useable on ANY map. We haven't had that selection since and thus we're confined to the limitations of each respective weapon class.
BO2 has simply brought this to the forefront and given SMGs a huge leg up with snakey, cluster**** maps that are smaller on average than we're use to.
I probably won't enjoy CoD to nearly the same degree as MW2 until they've reintroduced SP and reinstated Ghost/CB to it's MW2 level. I don't give a **** about the perk diversity argument. I used and saw EVERY perk on a regular basis back then (save for scrambler) and that's due in part to the original IW's weapon design/perk/map design proficiency.
I'd play Derail, Rundown (my favorite map actually), Karachi and Wasteland 24/7, before playing the entire playlist of BO, MW3 and BO2 together, if I could.