Wow, I had no idea haxe was still around. I looked at using it about 4-5 years ago and dismissed it as not ready for prime time, but that looks like a reasonably active community.
Honestly I'm quite surprised that it hasn't taken off more - the language itself is very nice and well-designed, and the way it handles multiple platforms is surprisingly elegant. The only real complaint I have with it is that the documentation is a bit disjointed.