Is it actually usable? Doesn't it use VNC?
I only loaded it up to see if it works. It does use VNC for the GUI. There are 3 versions of Ubuntu images that one can load- the core image, which is just core Ubuntu, but does not have a GUI ; the small image, which has a light GUI and a few apps ; and a full image that has the main Ubuntu interface and has apps like OpenOffice. I loaded up the small image, mainly due to space constraints on my GNex.
The small version runs better than I expected it to. I find it pretty smooth, as far as navigation is concerned. It comes with Chromium ( Google Chrome) and Firefox browsers installed. Chromium for me, has been unstable, but Firefox runs very well. I believe it has mouse support ( I could be wrong) . I would love to hook up to a monitor or TV to explore more,but I don't have an HDMI TV or monitor right now.