Or $130 used 9700P from Crucial.com. The games in
Hardware.fr's tests certainly seem to favor the R300 architecture over the FX's, though there are certainly valid advantages for a 5900XT (OGL games, Linux, multimon, lower idle power draw). But I don't think I'd recommend a 5900XT over a 9700P. Sure, you're taking a chance on any used card, but as long as you don't OC, I don't see why that 9700P couldn't last you at least a few years.
If you must buy new, just wait for an AGP 6600GT. I wouldn't pay anywhere near $200 for a 9800P with a 6600GT a few weeks out, but I'd probably pay the premium over a 5900XT (as HW.fr's numbers show a 9800P is ~30% faster than a 5900XT).
The choice mainly falls to what games you play, and what settings you prefer. AA+AF and D3D favors a comparable ATi card by a lot. If you believe
The Inq's latest numbers the D3D gap will grow with 3DM05, with a lowly 9600XT beating a top-line 5950U by 20%.