On the Linux side, changes include support for X.Org 7.2, letting you update to the official 7.2 from the RC if you were using it. Some fixed issues include the ATI control panel installer working properly, multi-display issues and a bug in the GUI-based installer. They also now have support for the 2.6.19 kernel. You can get the 32bit Linux drivers here.
On the Windows side, changes include enhancements to CrossFire that enable AFR, which will cause CrossFire supporting applications to get a performance boost and additional CrossFire support for newer titles. Issues in various games were included and many bugs in the Catalyst Control Center were fixed. You can download the new Windows XP drivers here.