A meeting was held today on IRC regarding Nouveau in Ubuntu's kernel. In particular, with Ubuntu 10.04 LTS planning to ship with the Linux 2.6.32 kernel, which has no support for Nouveau, it's to be decided what DRM code to back-port into this Ubuntu kernel. The entire drm-next tree (the DRM code that will appear in Linux 2.6.33) could be pulled in, but that's risking more regressions and other graphics updates outside of the Nouveau driver (though we would love for this pull to happen!), or to just manually pull in the Nouveau-specific patches. This specific matter is to be discussed more at tomorrow's Ubuntu kernel meeting. The drm-next patch-set weighs in at about 2.9 megabytes of code.
Also being decided is whether to pull in all of the Nouveau code now and then pull in a more recent DRM snapshot when the Ubuntu 10.04 release nears, or whether to just selectively pull in new patches. Whatever the case, the first alpha freeze for Ubuntu Lucid is happening next week so expect some Nouveau DRM code to get pulled in shortly so that it will be present for Ubuntu 10.04 Alpha 1.
The IRC log from this Nouveau discussion can be found on the ubuntu-x mailing list.