>> everything that uses the ati driver supports KMS now, modulo bugs
> Like the intel driver supports i855?
No, no such chip-wide breakage in the ati land. I've r200 working fine, and r100 is reportedly also pretty ok (for the class of hardware it is) under KMS. I've also r700 with the ati driver without a hitch and more stable (that is = stable) than the proprietary driver.