Hell Yeah...
This is going to be great when you finish! Obviously you needs some punch and kick noises in there somewhere.
A suggestion would be to add some sort of a Panic attack that you can only use once or twice per level. An example that comes to mind right away is that Zeebarf/Tom Fulp Disordery game, where you can jump kick to knock everyone down. Ever play Streets of Rage for Sega Genesis? That's another good example...
The controls are a little awkward, but understandable since you're making it a two player game. I just don't like having the movement controls and attack controls so close together.
Looks badass...once this is done, it will definitely make front page. You should have both Fulp brothers in there and give it a Double Dragon theme!