What's so odd about this is that I have this on my macbook now but in a much more straightforward way. Each application running that outputs sound has a volume control embedded in it (itunes, vlc, flash video in youtube, etc). I go to each one and adjust the volume. Not that hard. I realize PA was trying to centralize and offer more, but it's a solution looking for a problem in most cases.

And I tried out 'airfoil' the other day (I think that was the name) that let me push out audio from different apps on my mac to 'foil speakers'? - basically other software running to capture and playback that audio. I can essentially run and manage just the audio portion of itunes on mac 1 from software on mac 2. And it 'just worked' (to reclaim the ubuntu mantra). Ahh - here: http://www.rogueamoeba.com/airfoil/mac/