I think Fight Night Round 3 is my only 1k Achievement point game. It's very easy to do. I'm a complete beast at that game when using the face buttons, I wish I could use them in online fights. As far as XBLA goes, I'd like to get the 200 points for Uno.
Yeah, all the GP on Oblivion, I havn't gotten close. Uno I'm short the bluffing achievement but otherwise i'm just real close to a few like Crackdown and Guitar Hero 2. No 100% on GP for a game yet .