The 2.6.29 is not released yet. The merge window is open.
Some preliminary information on it are available in the following links :
[http://www.heise-online.co.uk/open/Kernel-Log-2-6-29-development-kicks-off-improved-3D-support--/news/112356 Kernel Log: 2.6.29 development kicks off, improved 3D support] (Heise online)
2.6.29-rc1 has been released. Interesting features: * [http://btrfs.wiki.kernel.org/index.php/Main_Page] BRTFS * [http://en.wikipedia.org/wiki/SquashFS] SquashFS * [http://www.phoronix.com/scan.php?page=news_item&px=Njk2MA] Kernel-Mode-Setting