The decision to stick with the Linux 2.6.32 kernel
rather than the soon to be released Linux 2.6.33 kernel
for Ubuntu 10.04 LTS that will be released in April is leading to a few more headaches for those involved with packing X.Org and the graphics components for the Lucid Lynx release.
Developers have already had to back-port the Nouveau DRM
that went mainline during the Linux 2.6.33 cycle in order to gain kernel mode-setting support for NVIDIA hardware in Ubuntu 10.04 LTS, but now it looks like they may end up back-porting even more of this Direct Rendering Manager (DRM) code for improved graphics support atop the Linux 2.6.32 kernel.
Bryce Harrington and others within Canonical and the Ubuntu development community have been discussing what to do about the kernel-side of the Linux graphics stack for this next Ubuntu release. For bugs that have arose within Ubuntu 10.04 already that pertain to the graphics drivers, the upstream developers are frequently telling the Ubuntu developers that the issues are already fixed in the Linux 2.6.33 kernel so to just use that instead. There is also support for greater hardware within the Linux 2.6.33 kernel DRM.
It boils down to three options that Ubuntu developers are willing to consider to address these problems and that is either 1. sticking with the Linux 2.6.32 DRM graphics code and just manually pulling patches when needed 2. pulling in the entire Linux 2.6.33 DRM atop the Lucid 2.6.32 kernel or 3. creating a Linux back-ports module on Ubuntu that has the 2.6.33 DRM available for those who need (or want) to use the newer code.
The first option would involve the most work on the part of the Ubuntu packagers, the second option would be best for those really into Linux graphics (i.e. Phoronix readers and us) and get excited about the latest code, but the third option is the most likely path to leverage the best of both options.
The discussion surrounding these choices can be followed on the ubuntu-x mailing list