Some things for those who don't want to watch the vid (NO spoilers):
In the Gamespot vid they play it on 1920x1080, which is perfect. Better textures, very good framerate that makes combat faster and more fluid. All around awesomeness. Everything looks sparper, but still falls behind the HD texture mod looks for DrS a little bit (I'm sure it'll be modded in a few weeks).
The dynamic lighting is missing, just like in the console version, flat lighting is present, looks much better than on PS. The pitch dark areas from the Network test beta build are gone, just like on consoles. It's partly a resource problem (had to tone it down to save performance), and partly a lesson from the beta: people shunned two-handed builds completely for the lack of lighting, and FROM did not want that. So, dynamic lighting and torch-heavy areas had to go. You can still do it, but it's not that neccessary. There's two areas where it's still quite important though, mirroring the Tomb of Giants area in DrS.
There's something I'm really pissed about: apparently button prompts are Xbox prompts still. I hope they change it quickly (with a release patch or something). Can't believe it's such a big thing considering how you can map anything anywhere out of the box…