Bah you're all missing a very important thing!
ATi is said to release a NEW video card shortly after the X1800 comes out, which it will come out I think November 5th, or already has come out I don't know.
BUt this new card by ATi, which is said to come out SOON, which I think means early 06', but, the G72 is coming out early 06' as well. I think this X1800XT is just to give ATi fans and nVidia a look at what ATi can do with 8 less pixel pipelines. Kind of makes you wonder what they can do with 24 pixel pipelines.
All and all, wait till at least March. I know I know it's a long wait, but the wait is sure to please everyone. With the new ATi card coming out, and the new nVidia card coming out, I think it's in your best interest to save your money to buy one of the new cards coming out in early 06'.