Kernel 3.4 came out with some rather interesting updates:
- btrfs performance improvements & better error handling. We're stepping closer to btrfs as the default filesystem.
- more GPU drivers. Of course, I'm particularly interested in the Radeon 7xxx & Trinity APU support.
- new x32 ABI for 64-bit mode with 32-bit pointers. A nice feature for apps that benefit from 64-bit mode but don't use enough resources to justify the larger pointer cost it entails.
- x86 CPU driver autoprobing to help identify the correct drivers to load for a particular CPU.
More details available @ Kernel Newbies Linux Changes page.