I am surprised by the lack of voting on this.
Anyway I gave it 9 out of 10.
Didn't play COD4 so this is all kind of new to me. (I know I am one of two people in the world who hasn't

)
Was not sure of the perks etc as it seemed to favour experienced players.
Having played it now for over a month my fears on that were thankfully not met.
Good campaign which does not outstay its welcome, generally good lag free mulitplayer, nice graphics, and Nazi zombies finishes it off.
Only complaints, not many (if any) mulitplayer online acheivements which I can understand why due to people playing games simply to get a certain acheivement.
Good stuff