So the press got a chance to play Pokken and there are videos on Polygon and Gamexplain and the like if you want to check them out.
More importantly, we got two new bits of information from this.
A new stage:
(which looks really cool, by the way,) and the character select screen:
What's important to note here is that while we already know Shadow Mewtwo is an unlockable character, the absence of regular Mewtwo seems to confirm it's an unlockable character too, (and it's probably going to be left of Chandelure on the CSS.) I also hope we get at least 4 more characters, the roster just isn't going to look right without 'em.