I'd love to. I've actually got an OSX build of the latest Making Movies (0.9.13), but since I don't have a Mac around, I can't test it. If anyone wants to volunteer, I'd be happy to drop a link for them.
Linux.. I've never actually tried. I did android (since I have an android phone), and in theory unity should work out of the box. But Theory is the kind of girl I'd never bring home to meet my mother, so... again, if I find a labrat helpful user that wants to test it, I can certainly order Unity to spit out a Linux build.