I got all achievements for oblivion on the 360, 1000 gamerpoints but sadly It was when I lost my main profile and created a secondary one that has no xbox live. But it feels great to complete the main quest and game.
All achievements, and the most fun, impressive RPG I've ever played. Sometimes wish I'd never bought it since it led to bad stuff, but that was nothing to do with the quality of the game.
Completed main quest, and all faction quests. got 1000 gamerpoints and I'm still searching for some abstract quests just to have a little fun killing stuff! :D