Few of you that have been following 360 news from Japan would know that ArcSys was working on 'strategy melee action' game for 360 for almost 2 years know and that Ishiwatari (creator of GG franchise) was behind it, so the actual news shouldn't be that surprising. Even though I thought that project was discountinued since nothing has been heard about it for a some time, maybe now there's hope for other small 3rd party 360 projects in Japan (Alfasystem, Cave, Treasure, Marvelous, Warashi, Moss...), eh?
As for the actual game I think RTS elements won't be that much incorporated into gameplay, and the game is more of 3d beat'em up with bit of strategy elements. Don't know why everyone is writing off the concept already.
As for proper GG2 game, it'll be probably mix of 3d graphics and 2d gameplay like Battle Fantasia, and we'll see it in arcades first anyway (TypeX2 board?).