Just to chime in with no cents at all, Java is all around this project as stated in the page above as well as the Android SDK, something to think about. Also Java is easily multi threaded, I can't see where for this little tool Java shouldn't be used.
That said, I know of Redtamarin but, .... java is ubiquitous with AS3 compilers.
Anyway, you can ignore this if Red Tamarin is something more than I think it is. π If Harman sticks around and still updates compiler/runtimes I am not ditching AIR "sooner than later" but using it for what I already do, Haxe is then something even more.
.. this is completely stream of thought, just a comment.