I get that the "CoD" formula has been tried, tested, and is true, but doing pretty much the exact same thing almost automatically guarantees you'll fail. The majority of CoD players are probably 1st prestige now, at least. (I'm just pulling that out of thin air, but it has been out for a while.) Why would they leave the game they've dedicated so much time to, gotten so used to, and jump ship to...the same thing, except now they lose everything they worked so hard for?
Look at all the WoW clones who tried that (I know, I know, different genre. But it's the same basic thing, isn't it?) and failed miserably. If part of you're strategy is getting players from an established fan-base to jump to yours, then you're heading for disaster. If players are going to leave a game, it won't be for the same game with a different name and paint-job, it'll be for a different game.
Anyway, that's how I see it. I'm probably wrong
And sorry if I spelled something wrong, :3 'tis late here.