That's amazing.
Funnily enough I'm using the voice recorder on my HTC to keep a quick and dirty record of musical ideas I have for my band, so I can review them later when I'm less drunk and knock up quick demos in Pro Tools of anything that I still like. This would be really cool - if it had brass voices it could cut out the demo production part completely.
I doubt my Hero has enough hardware grunt to pull it off though, even if the app does come to Android.
Come to think of it, any multitrack recorder app would be super nice - could beatbox into it or whatever.