Hard to say whether anyone will be purchasing them when final specs and pricing have not been announced. 😕
If you're looking to spend $500+, it's probably worth waiting for ATI's announcement in the next week or two, but I wouldn't advocate holding out for G71 (which may not be out/available until at least March). Otherwise... probably not worth waiting (although the 7800GT/X1800XL/7800GTX/X1800XT will get cheaper. Eventually.)