The X800PRO will be replaced with R430, a new chip on the block, but we suspect that this chip might be very similar to the X800XT PCIe, the R423. The only difference might be the production process as we expect to see this chip built at 110 nanometers. We still don’t know exact details but we know that this chip is real.Somewhere in Q1 2005 ATI will launch a R480 bridged down to AGP with its RIALTO bridge chip.
As for AGP users, ATI won't offer anything to replace the X800XT Press edition, X800XT and X800PRO at least for a while.
More info at The Inquirer