"In 3Dmark06 the HD 4850 can score 13,500, while the old 3850 scored about 8,700 in the same test. If you put two 3850 in Crossfire you will end up with 12,700; again, a score that is slower than a single Radeon HD 4850.
Two Radeon HD 4850s will score around 18,000 points on an Intel-based high-end machine. 13,500 is a great score, as a dual chip HD 3870 X2 card with 1GB memory will score 15,500, which is not that much better than the 13,500 scored by the Radeon HD 4850." (Fudzilla.com, June 2008)
We're looking at $400USD less than the GTX280, and an extremely close match. I for one am hoping the Radeon HD 4850 is better than the 260, and tailing the GTX280 (And that those scores are real). That would mean something amazing for ATI/AMD that we haven't seen for many years. AMD/ATI will have a better card.
How naive of NVIDIA to think they were the "niche market". Who cares if it has ultra-super-duper hardware. Look at damn AMD/ATI, if they hold true to their "GDDR5 memory" for the 4870, NVIDIA will surely hide in a corner.
Price
erformance NVIDIA! Not all of us are rich billionaires.