While X.Org Server 1.10 has been out since February, AMD missed supporting it
until it came time for Ubuntu 11.04 and then late last month they ended up dropping a Catalyst 11.4 pre-release
to Ubuntu Natty users. Today is the official release date for Catalyst 11.4 Linux to anyone interested. This contains back-ported X.Org Server 1.10 support in order to function with Ubuntu 11.04, Fedora 16, Arch Linux, etc.
The Catalyst 11.4 Linux driver also offers the first bits of AMD PowerXpress support
under Linux, but it's clunky in that the X.Org Server needs to be restarted when switching graphics adapters. This implementation is meant for switching between Intel and ATI Radeon graphics.
This driver also provides support for Red Hat Enterprise Linux 5.6 and SuSE Linux Enterprise Desktop 10 Service Pack 4. The Catalyst 11.4 Linux driver also has at least one fix for Wine.
The Catalyst 11.4 driver can be downloaded at AMD.com
for Windows and Linux.