Well, how soon do you want/need this video card?
If you can wait a while, I really think the Radeon 8500 will be da bomb. Waiting for new drivers/updates can be a pain, but in the end, I think it's worth it. Even waiting a week or two could show that this card could be, as many have stated, a GF3-Ti500 killer. Even the technical specs of the Radeon 8500 slap the Ti-500.
If you want it right now, the GF3 Ti-200 is sure a nice bang for the buck.
In my personal opinion, I'd wait another two weeks. Then see what the Radeon 8500 has to show.
Good luck!