while that would probably be a question better posed on the ubuntu forums, I will say that since Android itself is a linux based OS, that It should hypothetically be possible to install a different distro seeing as windows CE is often found on this same hardware. I would imagine if you could make an Ubuntu based ROM then you should be able to do it.
Thanks VonSpyder. So I created a bootable sd card with the latest Ubuntu and latest Android. When I restart the tablet it goes straight to the default Android OS . Any idea on how to force it to boot from my sdcard. I used Universal USB Installer – Easy as 1 2 3 | USB Pen Drive Linux to create the a bootable sd card. I seem to be missing something.