This pull request brings initial support for Intel Ivy Bridge (the next-generation 22nm successor to Sandy Bridge that's launching before year's end) and "hopeful" RC6 support. This Intel code is also working better for me with Sandy Bridge support overall after the last-minute SNB fallout in the Linux 2.6.39 kernel pertaining to semaphores.
The Nouveau driver has rewritten engine support for adding PCOPY engine support. The PCOPY engine enablement may be useful for the multi-GPU PRIME rendering work.
Within the open-source AMD Radeon driver there is namely a DisplayPort overhaul. David Airlie mentions this Radeon DisplayPort (v1.2) work is in preparation for supporting AMD Llano APUs in this open-source Linux driver. There's also more Cayman and Fusion fixes.
Besides the Intel, Nouveau, and Radeon enhancements, the DRM core has updates for 30-bit color support and there's also the initial MXM GPU switching support on NVIDIA hardware, a.k.a. the early NVIDIA Optimus fun. The VGA arbitration code has also been improved in the process.
The DRM pull request for Linux Gardenshed can be found in this mailing list message. David Airlie's Linux "Gardenshed" reminds me of AMD Treebark.