While the AMD Radeon DRM driver changes are exciting with dynamic power management and Sea Islands support, and the Intel driver has an assortment of good stuff, the Nouveau driver sadly isn't too exciting. The pull for the Linux 3.11 kernel still doesn't have Fermi/Kepler re-clocking or any other major changes to the Nouveau driver.
The Nouveau DRM changes just include various fixes that could benefit running Piglit concurrently, making buffer object deletion no longer synchronous (at least maybe a possible performance win?), and context/register initialization updates to resolve some stability issues. The only end-user feature for this reverse-engineered open-source NVIDIA driver in the Linux 3.11 kernel is the H.264/MPEG-2 video decoding support via the VP2 engine on some PureVideo HD graphics cards. Read that Phoronix article from a few days ago for the details on Nouveau supporting the VP2 engine, which also requires user-space updates to the Nouveau Gallium3D code.
There's several thousand lines of changed code in the Nouveau DRM for this merge window and the merge can be found to drm-next via this Git commit.