I've just recieved my Dell Inspiron 6400 with Ubuntu preinstalled. Almost everything worked flawlessly out of the box, but there were two oddities:
- The system has a widescreen-ratio monitor, but it came configured with a resolution of 1024×768. This resolution doesn't fit either horizontally or vertically — the physical resolution of the screen is 1280×800. Fixing this was a simple matter of installing the "915resolution" package from Synaptic, so I'm not sure why Dell doesn't do this before shipping. My best guess is that they use the same Ubuntu image for their non-widescreen systems.
- The system came preinstalled with Ubuntu 7.04 Feisty Fawn, but the CD in the box is for 7.10 Gutsy Gibbon. I promptly upgraded to Gutsy anyway; I guess they've just not updated their system image yet.
Other than that, everything just worked. The volume and brightness controls on the keyboard even integrate with something in GNOME (I'm not sure exactly what) that displays a little dial onscreen. The non-free drivers necessary to support the modem and the wireless network card were pre-installed. No preinstalled third-party junk, either, which is a refreshing change from Dell's Windows machines.