For Ubuntu 11.04 we do not yet know if the upstream ATI/AMD Catalyst driver will work with "Natty Narwhal" and its Linux 2.6.37 or 2.6.38 kernel and X.Org Server 1.10. As of right now, the Catalyst 9.12 / 10.1 driver does not offer up this support. However, over the weekend we see from the Ubuntu-X mailing list, AMD is certainly working on the xorg-server 1.10 support.
While X.Org Server 1.10 is past its feature merge window and is set to be formally released next month, earlier this month there was a second ABI breakage in this code, which causes issues for the proprietary drivers. The xorg-server-1.10 snapshot currently being tested for Ubuntu Natty isn't new enough to have the code for this latest break. This led AMD's Felix Kuehling to ask about it.
There is a recent ABI breaking change in Xserver git in the Xserver's ScreenRec structure that still seems to be missing in the Xserver 1.10 snapshot currently in xorg-edgers: http://cgit.freedesktop.org/xorg/xserver/commit/?id=e65c3f8bcc86845f21ac575e2bfb4b21b67d5ebf
This prevents my driver built against the latest Xserver headers to run on Natty with the xorg-edgers Xserver 1.10.
Are there plans to update the binaries in xorg-edgers to the latest Xserver ABI before they go into Natty's main repository?
Is there a known deadline for an ABI freeze of Xserver 1.10?
So it seems that AMD is already working on the X.Org Server 1.10 support, but they're waiting on an updated Ubuntu X Server package this time so that the latest headers will be in sync with their binary. It will be a question though of when this support lands if it will be here with Catalyst 11.2 or Catalyst 11.3 or if AMD will once again be shipping a special driver release over to Canonical for use in Ubuntu 11.04 when released this April.