I thought the demo was pretty good, on pc that is. The framerate was fantastic, graphics were great and there were no bugs that I could spot in my playthrough. So clearly the focus has been on the PC for this title, for a change, which isn't bad.
Only real complaints I've heard are that the demo was too closed off, which not a lot can be done about as it clearly is the tutorial island and probably the best way to demo a free roam rpg. And second that the leveling is too streamlined, e.g. Mass Effect 2. However its what floats your boat at the end of the day.
Tbh I didn't find the game much like risen at all, man THAT was a mess, not so with this. I've pre-ordered anyway, 19.95 on pc - can't really complain.