Linus has just released Linux Kernel 2.6.38 in time (it was predicted by many people due to his comment on RC8 release which should have been a final release, but he wanted to make sure nothing breaks) and it's out there but mirrors are still working to get the new release. Please wait for few hours before your mirror site start serving you with this just-released, fresh-from-the-git release.
Information about the new Kernel can be seen on KernelNewbies if you prefer human-readable format or more detailed and complex Changelog from Kernel.org.
What's so interesting with this new release is the new Automatic process grouping (a.k.a. "the patch that does wonders") that is reported will increase your performance significantly, mostly for multi CPUs. Other things that is also interesting is VFS scalability by Nick Piggin. There are still others, such as Btrfs LZO compression, read-only snapshots, Transparent Huge Pages, B.A.T.M.A.N. Mesh protocol, Support for AMD Fusion Graphics, and Dirty memory limits in the memory controller.
I'm downloading it now, but i won't install it until next NVidia and VMWare release is ready and support this kernel