The Linux 3.6-rc2 kernel was released after two weeks rather than one due to Linus Torvalds' travels. He was conservative in what he merged outside of the 3.6 merge window so a number of pull requests were rejected until Linux 3.7 -- he's being strict about only wanting critical fixes.
There's 330 commits for 3.6-rc2 with the changes being spread around the board but DRM/GPU and tools/perf updates standing out in particular.
The Linux 3.6-rc2 kernel release announcement can be read at LKML.org.
New features to the Linux 3.6 kernel are covered in this article.