XDA developer AdamOutler and loglud has been hard at work getting Ubuntu with Desktop lightweight LXDE interface running on the Nook Tablet. The whole shidoozle is a work in progress at present but word has it that a ROM should be available soon for unfearing Nook owners to toy with.
The implementation as is is by no means perfect, and sees Ubuntu run from an SD card and accessed via a VNC client, but it does look promising
Good Job XDA developer
See video Demo about ” Ubuntu Running on Nook Tablet” below