Graphically there's been HUGE changes since the demo! What you see in the demo is close to a year old. Since then, on the code side, we have added a ton of of stuff, including motion blur, godrays, reflective/refractive surfaces, and improved anti-aliasing. We've improved the lighting, improved the depth-of-field code, and fixed some problems (present in the demo) with the texture streaming to ensure hires textures are correctly streamed in at all times. We added additional features to the shader system to allow the artists to create even more impressive looking materials. to the shader code. We greatly overhauled the shadows. We also spent a lot of time optimizing the code, and the artists and designers did a fantastic job optimizing assets from their end. There's probably lots of other things I'm forgetting off the top of my head, but,in short, the demo is a pretty poor representation of the final game at this point; the final game is way better in every aspect! We badly wanted to release an updated demo that properly reflected the much improved state the game is in now, but we just ran out of time. It came down to a chouice between an updated demo and additional polish to the final game, and we went for the polish!