Seeing as the planets have been dropped in favour of larger mini-ships, I wonder how successful the planets were. http://www.brickset.com/browse/themes/?theme=Star%20Wars&subtheme=MicroFighters
That said, the concept of a mini-build and accompanying figure is a fun one.
I always though the Heroica board game line would have been a lot stronger if the games had come with perhaps one minifig scale version of the microfig characters. eg Barbarian, Wizard etc.
People love minifigs, as seen by the success of the CMF line, and the fact that random figs are crowbarred into sets to boost sales (eg Star Wars).
This would be a great way to see some of the LOTR/hobbit characters that people really want appear. With accompanying micro build of Minas Tirith or whatever. Great to put on your desk.
Less talking, more MOCing.