Linus Torvalds has announced the release of Linux kernel 3.12. Although the latest kernel does not come with any revolutionary new changes, incremental improvements to existing components should enhance graphic drivers, streamline power usage, and provide better filesystem support.  
The new kernel comes with performance improvements to pen-source graphics drivers for ATI and NVidia cards. Changes to the CPU freq governor that regulates the CPU frequency should bring improved energy usage. According to benchmark testing by Phoronix, some Linux games run up to 90 percent faster with the Radeon driver.
Intel's Haswell architecture now supports a deeper sleep state and faster wake up. Changes to /dev/random improve the initialization of the kernel entropy pool for better encryption. A new and still experimental RenderNode infrastructure for DRM aims to accelerate computation and rendering. The ext3 file system can access an external journal, and the XFS filesystem now supports user namespaces. After some repairs, the Lustre filesystem is activated, and the outdated /proc/acpi/event interface has been removed.
Torvalds also used the 3.12 release to start planning ahead for Linux 4.0, stating that he wants to limit the number of incremental 3.x releases. "I'm OK with 3.<low teens>, but I don't want us to get to the kinds of crazy numbers we had in the 2.x series, so at some point we're going to cut over from 3.x to 4.x, just to keep the numbers small and easy to remember …. I would actually perfer to not go into the twenties, so I can see it happening in a year or so, and we'll have 4.0 follow 3.19 or something like that." His main point was to pass on a suggestion that one release might be for stability and bug fixes only, with no new features or other improvements. Linus was originally skeptical about a bug-fix-only release but is contemplating it as a possible milepost for launching the 4.x series.
If you want to download the new kernel 3.12 and compile it yourself, you will find it on Kernel.org.