A demo for Panzer Dragoon spiritual successor Crimson Dragon somehow made it on to the Japanese Xbox Live Marketplace and before being removed, YouTube user Draikin1 managed to download it and record a playthrough, viewable above. This slice of gameplay isn't exactly new, having been reportedly playable at PAX East 2012, but its inadvertent release is curious.
I had completely forgotten Crimson Dragon hadn't come out yet. At this point, it could either be one of the last "core" Kinect games or one of the first motion-controlled titles for the next Microsoft console -- either option seems plausible to me. While I don't see a game like this achieving mainstream success as is, it could probably perform well enough given that it was an Xbox Live Arcade title, last we heard. A decent-looking one, at that.