According to the latest rumours ATI will launch a few mid-range PCI Express 3D cards in June. These cards only support PCI Express, they don't support AGP anymore. There will be a X600 and X600 PRO for the mid-range market, these are the PCI Express brothers of the Radeon 9600. The successor of the Radeon 9200 would be the X300 SE.
In the second half of this year ATI is expected to launch new high-end PCI Express graphics cards. The PCI Express variants of the X800 PRO and X800 XT are at the moment dubbed R423 PRO and R423 XT respectively.
It's also expected that ATI will launch the successor of the X800 before the end of this year. This PCI Express chip is codenamed R480.