Paul Davis, a Linux luminary who developed the JACK streaming protocol and currently works on the Ardour DAW (digital audio workstation), speaks at a conference here (video embed -- start at 2:22:32).
Worth a watch, even if it's pessimistic overall about Linux audio. On the one hand he offers a necessary reality check to open source boosterism, but on the other, he needs to insulate himself from ordinary bonehead users on forums, they are clearly wearing him down. (He's even testier on the forums.)
He makes a good point about certain types of software only being viable in the commercial realm, as opposed to the open source model. His example is Elastique Audio, a proprietary timestretching algorithm. He admits that neither Linux nor anyone else offers anything as good. It excels, he argues, because the creators spent ten years "polishing and polishing" the code. You need a promise of return, and not just the love of your peers, to do something that numbing.
At one point he muses on the types of audio users who might be drawn to Linux environment. An impetus he missed is people fleeing Apple and Windows for political and aesthetic reasons. Getting away from computer companies that trick you, spy on you, and bleed you for additional services is a strong motivator.