While there's many ongoing improvements for Intel's Sandy Bridge graphics and the next-generation Ivy Bridge graphics within the Linux kernel, Mesa, and xf86-video-intel (namely the SNA acceleration for the DDX), here's some benchmarks from two older Intel systems using the latest Linux 3.1 kernel to see if there are any improvements there.
This article provides a round of Linux OpenGL benchmarks from an Intel Atom 330 + i945 graphics and Intel Core i3 Ironlake system. The Intel 945 graphics testing was done with every Intel kernel release going back to Linux 2.6.35 (except for Linux 2.6.38 due to a Intel DRM issue on that release) and for the more modern Ironlake system it is testing every major kernel release back to Linux 2.6.39.
Ubuntu 11.04 64-bit was used with Mesa 7.12-devel git-0110aa0. If you are interested in just Sandy Bridge numbers, see the Intel SNB articles index on Phoronix. There are also some new Sandy Bridge Linux tests coming up soon. Simply put, however, for older generations of Intel graphics there are not any improvements in the i965 DRM to see with the Linux 3.1 kernel with much of the Intel developers now focusing upon just Sandy Bridge and Ivy Bridge. These numbers are just being put out there for reference and discussion.
Visit OpenBenchmarking.org to see these results.