Platinum Games (MadWorld, Bayonetta, Vanquish) next game will be a multiplayer online beat 'em up (it'll still have a single-player, but multiplayer was the focus), something that's never really be done before. At current the roster consists of several MadWorld characters along with several original characters. While nothing has been confirmed, I say it's likely we could see other PG characters from the likes of Bayonetta and Vanquish characters make it in, but that's just speculation.
The game is set to release later this year. Here's a batch of videos consisting of two teaser trailers, character trailers, and an interview.
http://www.youtube.com/watch?v=O-tOAXKwkDs Interview with gameplay.