I've been reading up on this game and it seems so weird. It sounds like they are turning it into a Ninja Gaiden 2 mod for Ninja Gaiden 1. They said the speed is now back at 100% (compared to more than 125% in NG2 for 360) and enemies now come three or five at a time instead of ten (like in NG1). There is other stuff like, supposedly, improved visuals (I guess they claim this despite having half as many enemies on screen, but whatever), a better camera, the purple essence crap instead of all the gore and more content.