Unfortunate thing is that we're in limbo at the moment. We have no idea if gf100/gt300 is weeks or months away. So the question here is exactly what ur budget is.
Being interested in $400 or more, even if u get a 5870 (u gotta find one also), their prices are hyper-inflated atm, and there are signs of 5970 being sooner than possibly the gf100/gt300. When it comes out, the prices may relax again.
Something is really going on the card manufacturing side of things for all gpu providers. There is an unholy lack of stocks everywhere - if ur an advocate of choice. Sure u can find 'a' card, higher price than normal, perhaps not the manufacturer u want tho.
I don't swallow the yield stories people are making up tbh. Something else is going on that we're not aware of. I favor a contractual dispute behind closed doors, possibly involving TSMC, but wholey not down to any production problems. They're making smaller integration cpus for other companies without issue.
People will however say u can w8 forever in the pc game.