The Radeon 256 looks like a really nice product, but I only have two complaints (well, these are pretty much the same complaints I had about the Fury 32MB when it was released):
1. It's too expensive. Expect to pay $300 retail for a 64MB DDR. Sure you're getting a lot of features for the money (like the hardware accelerated DVD and Rage Theatre chip), but if they're going to compete in a market like this, price will give them one of the biggest market advantages.
2. I'm still skeptical about driver quality. I mean, the Rage 128 has been out for a year and a half and there's STILL driver issues with OpenGL, as well as lacklustre 16-bit rendering performance. Granted that the Radeon 256 is a very different beast from the Rage 128 (designed from scratch), I'm still just a bit weary about the quality of the drivers that will ship with the final product. ATI has never been very fast with their driver updates, either.