The Linux 3.12 kernel is now up to its fourth release candidate / pre-release. As is always the case, these RCs don't introduce new functionality but are out to address bugs. Linus is a bit turned off by the fact that 3.12-rc4 actually has more commits than there were in 3.12-rc3.
Sticking out in the Linux 3.12-rc4 kernel is lots of file-system driver fixes. If you missed it, you can already see our Linux 3.12 file-system benchmarks.
More Linux 3.12-rc4 release information can be found out via the mailing list announcement.