Hello there, I am a sometime BeOS user and music producer/recording engineer.
Recently, Reaper, a Digital Audio Workstation suite, has been making waves amongst pro-audio engineers. Many are talking of switching from one of the flagship industry-standard audio packages in the near future.
http://www.cockos.com/reaper/
At the moment, Reaper is Windows only, with OSX to follow soon.
It seems to me from my limited knowledge of Haiku, that Reaper could be a great application for the "new media OS".
Would it be worth someone from Haiku contacting the Reaper developers? I for one think it could be very promising, and I urge you to take a look.
Kind regards.