Okay, this is just a initial impressions review, really. I've only played for maybe twelves hours total and a lot of that was redoing bits after being killed the first (Or fourth) time.
Firstly, it is probably the prettiest PC game yet. My machine is only a touch over the recommended spec, and I have been too scared to try and max out the graphics, but on the ones it picked for me... wow. It gets you with little things, like walking through knee high grass and bushes, which look pretty much real. And gazing down onto the Imperial City at sunrise is just astounding. There is one big "...but" here - the facial animations when you talk to people are really bad. The faces themselves look good, but the movement's just wrong - like talking to a latex puppet. After Half-life 2, this is just terrible.
The system and quests are just like Morrowind (my only previous exposure to the series) and that's fine. For some reason they decided to scale how tough things are to your level, which means the level of difficulty is consistent all through. Why they chose to do that instead of "remove leveling", I have no idea. So far, quests and exploration have been fun. I did the first few pieces of the main quest and then decided to take a break and explore. It's all good stuff.
Also, it's nowhere near as buggy as any of Bethesda's other games has been. Not unbuggy, by all accounts, but I am unaffected. Strictly speaking, I am - it crashes every time I exit the game - but not in a way that affects my play.
Buy this game, unless your machine can't run all the pretty stuff.