Runs great on my end too. THough I use 1600x1200 currently. Runs great with an exception here or there. Using the Chuck patch makes thing even sweeter. HDR, 4x AA and 16x AF @ "Ultra HIgh" settings. I can change the settings a little bit but Oblivions default graphics settings for my rig are good enough.
BTW, I Use all kinds of mods to make the game look even better and still no problems. Indoors is still above about 45 FPS.