My opinion to the Skyrim trailer is similar to what I felt about Dragon Age 2 demo. For a sequel, I expect to see some visual improvements over its predecessor, but all I see is what look like Oblivion with better shaders. I have seen Xbox 360 games with better water physics, better shaders, so the problem does not lay with the console. Just disappointed. :sadvaultboy:
Hopefully, the textures will be improved, because really, that's about the only thing in the trailer that looked kind of rough, If you look carefully, every texture in the trailer appears to be lower or equal in resolution to Oblivion. I suspect that's due to memory on the consoles, and hopefully that will get resolved. Even with the low res textures, though; the game footage was impressive.
I've studied the trailer fairly carefully, and I'm actually impressed with the improvements. The trees were amazing - in several scenes, you can see them swaying in the wind realistically. The rapids, while not great looking, do feature splashing that wasn't present in previous games. The actual water itself can probably be fixed with a better texture. Likewise with the Dwemer ruins. The subtle steam effect was very nice, even if the textures were a bit bland. (that could have been lighting, though)
One of the most promising things I saw was the cavern being lit with magic. (the first sequence, with the blue crystal in the background) It appears that the Oblivion lighting issues have been largely fixed. The cavern was very dark prior to the magical effects lighting it up, and that is a good sign. It means that lighting is going to be important again. The second sequence with the fireball was also impressive. Spell effects have been stepped up a notch.
Also, I really liked the ability to dual-wield both spells and weapons. This will make playing a spell-sword doable for once.
Over all, it looks like the console version. Most of the low-res texture issues won't be a problem on a screen several feet away. Todd already stated that the PC version will get higher res textures, so this may be a moot issue.
What we didn't see, and I am hoping is present, is dynamic water that actually pushes things. It would be nice to see animals/NPC's/you dragged down a raging river. We also didn't see any environmental hazards, which I'm also hoping for. (specifically, hypothermia and snow blindness)