2 (with DLC) > 1 (with expansions) > World at War/3 (pretty equal, in my opinion) > Black Ops (other than Hanoi, Nuketown, Firing Range, and Summit) > Big Red One/Finest Hour/Final Fronts > 4: MW > most of the DS maps (a couple are great, even if they were console maps) > MW2/BO2 >>>>> MW3
Those who disagree by more than one position on this hierarchy (the difference between 2 and WaW/3 on my list) don't know good map design. Symmetrical maps are lame, and YES, it IS possible to have asymmetrical maps that are good and fair from all angles (see 2-Black Ops on my hierarchy; Overgrown from 4 is another good map).
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