I recently upgraded to a GTX570 from my 8800gt/9800gt. It's being held back a bit by my Q6600 but that's ok. It's still kicking strong so no need for me to upgrade. I sure am loving BF: Vietnam at 1920x1080 with everything cranked and 16xAA/16xAF. Hell, it never drops below 60fps so it's all gravy. For the resolution I'm running things at, it's just about perfect.
Battlefield honestly doesn't look that much better in comparison to when I was running it with all medium settings at 1080 with no AA but I notice no slowdown when smoke is around now.
I've also got a new pair of Sennheiser 595s on the way!