Intel's Q1'2010 recommendations include xf86-video-intel 2.11.0, Mesa 7.8.1, libdrm 2.4.20, the Linux 2.6.33 kernel, and X Server 1.8.0. Also being recommended by Intel is Cairo 1.9.6 and Clutter 1.2.4. The recommendations can be found on the Intel Linux Graphics web-site.
Most distributions like Fedora 13 that are updating around this time are shipping with packages similar to these recommendations. Ubuntu 10.04 LTS though is using Mesa 7.7, the Linux 2.6.32 kernel (but with the 2.6.33 DRM back-ported), and the X Server 1.7 series.