A great game, but a struggle for some.
Firstly, the graphics. Definitely a high point for the game, the visuals are stunning. For 360 owners, this is a great showcase of what can be done with the console's power. Good draw distance, excellent models (even to a point where they are too realistic to some) and great lighting and other things make the graphics truly awe inspiring.
The sound in the game is very similar to the graphics. A nice, ambient score, which is good enough to play to, but not everly distracting. If you don't like the tracks, then put on your own even. The voices are good as well, with realistic voice acting, if a little corny and at times repetitious. At one point I attempted to follow one person around to find out how they interacted with the world. I realised very quickly that he repeated quite a lot of dialogue, and some of it didn't make sense. Such cases are rare in game though, and it's not a serious loss.
Gameplay. It makes or breaks the game, and i found that Oblivion's gameplay is highly subjective. Many feel that it is a "all work, no reward" game where a player continues to level, do quests, but with no real sense of satisfaction behind it (i personally fall into this category). However, i know plenty of people who found it much more engaging than I. For me, it did get boring after about 25 hours, but this is only for a few people i believe. It is definitely a improvement from Morrowind, as the combat and other such facets of the game have been made much more engaging.
All in all, I wasn't truly satisfied with the game. It is a great experience, but for me, that expiereience quickly wore thin after about 25 hours, at which point the game became repititous and somewhat dull.