The Nouveau 2D driver performance used to be very good against the proprietary/binary NVIDIA Linux driver. After running the new Intel SNA benchmarks earlier this month, I ran some quick 2D benchmarks of the latest Nouveau driver and NVIDIA binary driver.
Testing was done from the usual ThinkPad W510 setup with the NVIDIA Quadro FX 880M graphics. The Linux 3.3 kernel, xf86-video-nouveau Git, and Mesa 8.0-devel Git were used on the Nouveau side. Additionally, the stock Nouveau packages from early Precise were used when still on Linux 3.2 and Mesa 7.11. With the binary NVIDIA driver it was the 290.10 release tested. X.Org Server 1.11.3 was used for both configurations along with the Unity desktop and other stock components of Ubuntu 12.04 Precise Pangolin.
Cairo Performance Demos, cairo-perf-trace, x11perf, render-bench, GtkPerf, and QGears2 were run on the 2D side. For some reference figures against the 3D/OpenGL results, OpenArena, World of Padman, and Lightsmark were also run in the same software/hardware configurations.