The basics would be the same as SF. Health meter, 3 level super meter. No fucking guard meter though, mainly because I hate the damned thing. (Fuck you Charlie. Damned world tour.)
Anyway, the main difference would be the "Rage System." Basically the more you get hit or if your punches get blocked, the more your rage meter grows. Max the meter, you can pull off a rage combo. The meter will slowly dissipate to zero unless you pull a combo, where the meter will automatically drop to zero. And only one until the meter's filled again. The meter will not rise if you land a hit however, but will in fact drop, so you can't combo something in normal mode, go into rage and then pull off a rage combo.
I don’t know if the rage system (Not my version, any one calling it rage.) is in use by any other games, besides the one CvS2. And yeah, mines a kind of variation on that one. :P