Ubuntu developers are looking for those NVIDIA customers to be testing their GeForce 7 and newer GPUs with Ubuntu for at least one hour per week using the latest development packages for Ubuntu 11.04 "Natty Narwhal".
Yes, this is testing of NVIDIA's official closed-source driver, so it isn't particularly exciting and any driver bugs end up just getting reported back to NVIDIA Corp while awaiting their developers to fix them. This isn't nearly as exciting or beneficial to the open-source community as the Fedora Graphics Test Week that happens once per release cycle where the latest open-source driver code for NVIDIA (Nouveau), ATI/AMD, and Intel is under focus, not the binary drivers for which distribution vendors have virtually no control over. Granted, it wouldn't be particularly beneficial to the Mesa / X developers to have a similar Ubuntu Graphics Test Week since Ubuntu Natty for instance is tracking Mesa 7.10.1 and not the much more interesting and latest, Mesa 7.11-devel.
Those interested in testing NVIDIA's "blob" driver for Natty can read this mailing list message, which links to this Wiki page.
Ubuntu's Jorge Castro mentions in an email to Phoronix that they are waiting on the ATI drivers for the next round to focus upon testing AMD's blob. Catalyst 11.2, the latest publicly available proprietary driver from AMD, doesn't support the Linux 2.6.38 kernel / X.Org Server 1.10 as used by Ubuntu 11.04. This means Catalyst 11.3 will end up supporting Ubuntu 11.04 when released in the next week or AMD will end up -- once again -- seeding Canonical with a Catalyst 11.4 pre-release in order to provide proprietary Radeon/FirePro graphics driver support prior to the Ubuntu 11.04 Beta freeze.