Kernel release status
Linus's pre-2.5.49 BitKeeper tree includes a number of module fixes, nanosecond time support for the NFS filesystem, an S/390 update, and a large number of other fixes.
The current development kernel prepatch from Alan Cox is 2.5.47-ac6. Alan continues to issue patches against 2.5.47 because "the 2.5.48 tree is a little bit too broken to run IDE development against."
The current stable kernel is 2.4.19. The second 2.4.20 release candidate was released by Marcelo on November 15; it includes a fix for the denial of service vulnerability and several other updates.
Alan Cox's latest 2.4.20 prepach is 2.4.20-rc2-ac2, which adds a number of fixes to the second release candidate.
Alan has also released 2.2.23-rc2, which is
primarily motivated by the denial of service fix.