It's here in video at least; I don't know why it isn't playable, as it looks really far along. According to the pamphlet I am not in a position to scan at present, the game's 60% done -- which was about where the original game was when I first played it.
Anyway! Details. Characters thus far announced include Kyo (in that outfit from the Production IG character sheet), a rather feminine Iori, K', Maxima, Seth (in a more grubby outfit), Alba and Soiree, Terry, Rock, Mai, Athena, Ash, a very Art of Fighty Ryo, Leona (with long pants), the Ikaris (both with new outfits), Chae Lim, a well-rendered Billy, a poofy-haired Kula, and new characters Nagase (a very yellow girl) and the adult gothic loli Luise Meyrink. I think that's all. I might have missed someone.
From the video, it looks like every character has either been remodeled or significantly edited. At the least, there are new textures and a few more polygons. Most of the animation seems to have been redone, and is much smoother than before. All the motions seem to blend into each other, continually. There are a lot more special effects, and the lighting seems to have gotten a lot of work. There's still a little way to go with the presentation. Not bad so far, though!
Systematically, it looks like there's some kind of parrying thing going on now; at one point, Rock and Terry are kicking at each other, and Rock sort of kicks Terry's leg out of the way. They trade blows in a really seamless fashion. The game is also faster and more... extreme than before. Lots of knocking people into the air and doing mean things to them. Again, it's all smooth. No jerking around!
There's a pretty decent rendered intro. Looks like it would have been state-of-the-art about five years ago. Ryo's face looks a little weird. That's all right, though. Very dynamic and well-choreographed, for the most part. The Production IG animation is really snazzy, and actually, for how short and random it is, has a decent sense of mood and emotion to it. At one point Kyo looks shocked at a turnaround in the middle of a fight he's in.
Altogether, the game seems to build significantly on what the previous one established.
Oh! To note, Max Impact 3 also was announced for Xbox 360. So I guess this series will be around for a while.
I whish I could be there 
