I've played about 20 hours, so far.
Overwhelming amounts of stuff to do. I'll run through the wilderness to a quest and a random stranger hands me another quest, which takes me off in a different direction, and before I reach that destination, I get distracted by something else.
Great attention to detail, no matter which direction you go.
Game looks and plays well. The UI is horrible and annoying, and the quest journal could offer more information.
The voice over isn't of the highest quality, but there is so much of it.
The dungeons are cool, as far as atmosphere goes, but a little too linear. Too many bandits and undeads, but maybe that changes later.
The AI is about as smart as a dull rock and can easily be exploited. Sometimes, they seem rather glitchy and don't even fight back. Your allies are often more in the way and extremely suicidal at times.
Playing on hardest difficulty, I have no trouble killing everything with my archery/dagger thief/murderer. Still, it's good fun. Though I'd like to try again, when the balance/combat tweak mods arrive.
A lot of the negatives were expected.
Overall, I'm having a lot of fun with it. Far more than Oblivion.