MATLAB runs in Ubuntu 12.04 without any major problems. However, one issue that I noticed was that changing the font size in figures has no effect; the text always appears in default (small) size in Matlab. The correct font size has an effect only in exported PDF and EPS files. The font spacing is incorrect though, as it seems to be based on the fonts that Matlab uses. As Matlab is often used (only?) for making figures, this can be a major problem.
As mentioned in this thread, the problem is related to Matlab not finding the correct fonts in Ubuntu OS. As a remedy install the following packages:
sudo apt-get install xfonts-100dpi xfonts-75dpi
and logout and login again. Matlab should now be able to show the plots in correct size. The fonts do not look pretty, though, which is probably related to broken anti-aliasing. Maybe there are other broken dependencies?
However, exported PDF and EPS files should now have the correct font spacing (e.g. the size of the legend box) and should be usable.