I dunno, all these "proven honest to gosh tests" that I keep seeing floating around the internet keep stating that the X1800 will cream the 7800GTX in every single benchmark/game available, and the same goes for all there lower cards compared to the 6800GT, and the 6600GT.
But isn't this what ATi does with every card release, hype up the "MHz!!11!!1!" and make it look faster, but as the informed keep remarking, "it still has less pipelines, all that power is being wasted on a 16-pipe card."
I think it will be neck and neck, they will probably outperform eachother in several benchmarks, making it a very hard decision to find the "best" card. But not nVidia is already planning to go with there "8XXX" line of cards, and ATi supposedly also has plans to release yet another line of cards after this new one hits the shelves. I tell you ATi is falling behind, planning one thing before what they are advertising has even hit the shelves yet.