O'Reilly LinuxDevCenter.com today has an extensive interview and featurette
on the development of the flagship power app for Linux music,
Rosegarden. Easily the most full-featured free application for music,
Rosegarden features MIDI and audio sequencing, effects, soft synths,
and even notation. I might take issue with the developers' claim that
it matches most functionality of commercial applications — there's
still no mixer automation, for instance — and it's Linux-only for now,
meaning you have Linux audio drivers to deal with. But for a free
application just nearing its 1.0 release, this is impressive work. It's
also fascinating to hear the wunderkid developers talk about what works
and doesn't writing in C++.