The current 2.6 development kernel is 2.6.29-rc7, released on March 3. It
contains a long list of fixes, new drivers for Atheros L1C gigabit Ethernet
adapters and FireDTV IEEE1394 adapters, and some out-of-space handling
improvements for the btrfs filesystem. See the
long-format changelog for the details.
There have been no stable 2.6 updates released over the last week.