Great RPG. Not for action RPG fans !
Most of the time I have spent outside of the main plot just woundering in the world, exploring and meeting new characters. This game is amazing, but keep in mind it was not created for action RPG fans. It's not fast paced game ! Playing it there is no space for haste... the best way is to simply play it as real RPG and "feel" you character.
There is so many things to do I have not even cleared half of them and there are already couple of add-ons available on XBL along with Shivering Isles on it's way! It does make this game VERY long lasting. I do return to Oblivion with great pleasure all the time which is the best recommandation I can give.
Go for it!