Kanru's been developing it personally, it's not an available technical preview edition. I vaguely remember him mentioning it; you'd want to check his twitter posts.wait really? I guess I might be behind but I searched around and I almost for sure thought a mac version wasn't available yet, since i didnt find one on the official synth v site.
If you did see mac demos, its possible that the poster used wine to use the program ... which doesnt work for me but it might work for other people. but im really hoping for a mac based download where i dont have to try and use wine.