At this month's GTALUG meeting, Steward Russell gave a brief introduction to the Amateur Radio Service and some of the software he uses in his Linux-based set up. Very few amateur radio operators use Linux, although Steward did not give any actual numbers.
The primary software for general communication is fldigi, which is free software and runs on Linux. However, Wine was mentioned several times, as the vast majority of software used by ham radio operators is Windows only, which is annoying but hardly surprising. The Industry Canada software used to take the license test, is one such example.
Steward also mentioned "software defined radio" (a phrase I first heard a few years ago from my brother, another ham radio geek) as the possible future of amateur radio but not everyone in the community is convinced. The amateur radio hobby is over a hundred years old and there are many curmudgeons who prefer the tried and tested over new fangled gadgets.