Oblivion
I hope that you have been playing Oblivion. If you liked Morrowind then you already have it :-). If you like the GTA style of game in a Fantasy setting, then you can’t go wrong with Oblivion.
The game is truly amazing, the audio is wonderful with dynamic music that changes when an enemy is around. The visuals are fantastic and the game is great. So far I haven’t even done anything for the main quest. I have just been going around doing quests here and there and experimenting with the game.
Lots of reviews around in the usual places CAD Media site has a great review of Oblivion that sums up how I feel about the game.
Gamespot have an Oblivion - 360 vs PC article. Short version - If you don’t have a high end PC, get it on the 360. For the cost of a video card to play this thing in high res, you can do it on the 360 and get a console as well :-)