While testing all releases from Linux 3.5 through Linux 3.10 Git, the results for the Intel HD 4000 "Ivy Bridge" benchmarks with the Core i3 3217U CPU found on an ASUS Ultrabook aren't too enticing. As far as the kernel driver goes, most major performance optimizations seem now mature for Ivy Bridge on the kernel-side. There's still ongoing improvements to the Intel Mesa DRI driver (including new Mesa 9.2 benchmarks for IVB coming in the next few days), but as far as the i965 DRM driver is concerned, there aren't many major performance changes on recent kernel releases.
As far as the Intel DRM driver changes that were queued up for the Linux 3.10 kernel, read this Phoronix article.
See the rest of these Intel DRM driver benchmarks on OpenBenchmarking.org. The new Intel Mesa benchmarks are forthcoming.