With World of Padman at 1920 x 1080, the 9500GT was 84% faster and its speed nearly matched the binary driver. The GeForce GT 220 was 80% faster with the newest kernel, but there was still a 39% difference between it and the binary solution. Like all the other tests, there's also a ~85% performance improvement with the higher-end GPUs, but the performance relative to the NVIDIA binary driver is still much worse. The GeForce 8500GT on Nouveau was unstable for this game.
When running Urban Terror, the 8500GT on the early 2.6.39 kernel code is faster than the binary driver while the GeForce 9 series and later there is still a measurable difference. There is though still a huge performance boost with the Linux kernel Git code.