I really enjoyed the demo and while the HDR is a bit extreme the other effects are excellent, in paticular the field of view blur; why don't other games use this, looks awesome! Some of the scenes with the concentration view on look better than any oblivion screenshot I've seen.
That said, it runs laggy on my system (A64 3500, 1GB, X1900XT). In particular the begining of the horse riding map, the trees and bushes really slow down the FPS, into the 20fps range. Even the loading times are ridiculously long.
Hope its just a driver issue or just poor optimisation in the demo, because I'm really looking forward to the full game.