RAM Digital Media, if you're not afraid of Nvidia, you could always grab the 8800GTS with 640MB (not the 320MB version). The performance is very good, the card seems solid, and the price isn't over the top. Performance compared to a X1950Pro should be double if not more (depending on the rendering scenario) and image quality should be better (more Antialias and Anisotropic modes).
Or, wait for the HD2950Pro ;)
EDIT: Apparently Nvidia is planning to boost the performance of the 8800GTS. So, waiting is the best option.

And here's a review of the HD2900Pro (french translated):
http://translate.google.com/translate?u=http%3A%2F%2Fwww.puissance-pc.net%2Fles-dossiers%2Fcomparo-hd2900pro-512-vs-8800gts-640.html&langpair=fr%7Cen&hl=fr&ie=UTF-8&oe=UTF-8&prev=%2Flanguage_tools
Or, wait for the HD2950Pro ;)
EDIT: Apparently Nvidia is planning to boost the performance of the 8800GTS. So, waiting is the best option.

And here's a review of the HD2900Pro (french translated):
http://translate.google.com/translate?u=http%3A%2F%2Fwww.puissance-pc.net%2Fles-dossiers%2Fcomparo-hd2900pro-512-vs-8800gts-640.html&langpair=fr%7Cen&hl=fr&ie=UTF-8&oe=UTF-8&prev=%2Flanguage_tools