I think what you're failing to see is that CoD, despite the yearly installments, is a quality franchise. The scores may not reflect how much fun you'll have with the game, but they do paint a good picture of how much a developer tried and succeeded.
Declassified is an example of a developer not trying and just throwing something out there.
Treyarch actually put some effort into BlackOp II and tried making changes without messing up the formula too much and it shows.
gamefan67's comments