Overall this week's Linux 3.6 kernel release candidate is fairly quite and "it's just fairly random" in terms of changes due to most of the kernel maintainers having spent the week travelling and at the various Linux Foundation events in San Diego, California.
"The statistics look a bit unusual, too, likely for the same reason. It's 40% architecture work (powerpc, x86, mips, arm), and 20% btrfs (late pull request of fixes, because I rejected an earlier bigger pull request). Just 20% drivers, mainly some drm updates (the bulk being radeon) and some block driver things (libata and drbd)."
More details can be found in Torvalds' 3.6-rc4 release announcement.