Just noticed about this recent release of JUCE 1.10:
You might remember then, that I've brought
this very subject into
attention to the Linux Audio Developers and USers (LAD/LAU) mailing
list, and to put a long story short: help is being here reiterated to
write the native Linux Audio and MIDI implementations of the JUCE C++
framework, which among other things, may bring a native Tracktion Linux
port into light :P
and if a developer adds native linux audio/MIDI to JUCE, they will still
have to pay for the linux version of tracktion, no?
That is probably one question that should be better addressed to Mackie,
but I would guess that the answer is yes.