Not from the developers, but from the Expanded Universe:
Dxun- Dxun, one of four moons orbiting the planet Onderon, is home to numerous bloodthirsty monsters. Due to Dxun's erratic orbit, several of the creatures were able to migrate to the surface of Onderon ages ago during a brief period in which the two worlds' atmospheres intersected. Four thousand years ago, after Queen Amanda of Iziz was defeated by the Jedi, the inhabitants of Onderon built a Mandalorian iron tomb on Dxun to house the remains of the Queen and the Dark Jedi Freedon Nadd. Exar Kun later visited the tomb, where the spirit of Nadd helped him discover some hidden Sith scrolls.
In the Dark Side Sourcebook for Star Wars D20, Dxun is listed as an example of a Major Dark Side site due to the corrupting influence of Freedon Nadd and the Queen. As such, an already dangerous place became much, much worse.
4 out 7 worlds are now known(Peragus, Dantooine, Telos and Dxun), but everyone of them has either got a 'dark' tone to it or it has experienced destruction in the past 10 years or so. I vote for a 'safe haven' planet as the next one to be introduced.