Well, assuming it's another Wii game (which seems likely, Capcom has been hinting at amping up their Wii support in some shape or form for a while), we already know about Monster Hunter Tri coming over, so that's out.
So, that said, it's likely either going to be a) something Mega Man related (MM10? X9? DASH/Legends 3....?), b) another nice "retro-revival" of some sort, or c) something completely unexpected.
Satuday Night Slam Masters/Muscle Bomber, complete with 4 player arcade-style action. Y'know you want it! :lol
Only Namco X Capcom is really viable at this point, and by this point in time, I'm pretty sure that if neither Capcom or Namco have made any hints of bringing it over by now, they never will.
The other games are much more complicated, in that their are a lot more licenses involved, and those who do hold those licenses can ask for much more in the way of money.
So, TvC was made possible, but I don't think it's time to start getting ahead of ourselves, just yet...