Well, for starters the No health abr thing is not a COD invention as far as i know. Many games have this.
Second, the multiplayer perks are awesome. it's like BF series unlocks and prolly a lot of otehr stuff in other games as well, which allow costumization to how your character/class works, integrating RPG elements like that is what makes me like MW2.
Also read moviebobs lates text about how people have become whiny bitches who'll call everything cliché. While he talks about movies its the same for games, everyone seems to have something up their ass, whenever they think they're smart, cause they noticed that some elements are seen in different games.