Metal Overlord
Smash Hero
They have patches for that.This will probably be very sparse, like once every six months to ensure full development of DLC characters and to balance them out with others that are already available. There's also the fact that you'll also need the ability to fight against DLC characters even if you don't have them.
Good question, I dunno, I thought I heard Ninty say a while back that they were against that idea? Then again, way back when, they said they were against DLC, too...[hey, do you guys think the WiiU will have achievements like XBL and PSN?]
As I said before, just make them timed-exclusive content to one system and have them available to both systems after a few weeks via a free update to your content or as free DLC.Having different rosters defeats the purpose of inter-connectivity, though. If you have an exclusive on one, you couldn't transfer them to the other.
I only support the version exclusives idea for Pokemon, though.