I agree that it plays better than the premise sounds, but it's basically a TF2 clone rather than a CoD clone. As much as I enjoy Batman-themed things, if I get the urge to play a multiplayer shoot-'em-up, I figure I'm probably better of sticking with TF2. It has hats.(I also dislike the fact that you have to buy skins for some of the fiction's more interesting characters with real money, instead of being able to unlock them.)
I can see that comparison but it really controls/moves more like CoD. At least on the controller, all the buttons are exactly the same (and while that's not a huge thing with most PC games letting you rebind keys its pretty noticeable on the controller), also all weapons have aiming down the irons and whatnot... Also there's no hard classes... Though it its certainly more class based than CoD.
As for the real money versus unlocks... Its been far too long but I remember being able to make some pretty silly characters with the unlockable choices.