I've been on the OpenAOS IRC for a few months (got my A43 in May) and I really bought it as a hacking toy. As a Linux fan and Ubuntu user, I wanted to get Ubuntu running on it and figured it would be possible based on other projects like BeagleBoard using pretty much identical hardware. With some help from OpenAOS, PandaBoard IRC, and the OMAP community I've finally got a useful Ubuntu image running. The system runs off an SD card instead of a filesystem image.
Kernel - I'm using Nicktime's 2.6.37+ kernel (http://dev.openaos.org/wiki/Gen8Linux2.6.37
Modules - The modules come with the kernel and must be copied to the SD card with root fs.
Firmware - The firmware files needed can be downloaded with git as shown here: http://www.omappedia.org/wiki/MAC802.11_based_Wilink
Root Filesystem - The root filesystem of Ubuntu was created with rootstock and has the Gnome desktop manager
WiFi, Bluetooth, and Touchscreen are supported, sound is working in the kernel but not in Ubuntu, and power management/graphics acceleration are not implemented yet. I have an identical Debian image that has sound working (Ubuntu uses PulseAudio, this may be a problem). Screen rotation is available by modifying the kernel (adding omapfb.rotate=1 to boot args) but the touchscreen does not rotate, so it's only useful with a Bluetooth keyboard/mouse. WiFi works under Wicd as well as Network Manager. USB Networking (g_ether) is also available, but USB host does not appear to work.
Here is a video demonstrating it:http://www.youtube.com/watch?v=RmSWF0iJWN0
I'm still working out the sound. I go back to college this week but I'll try to post my filesystem and kernel if anyone wants them to try.