We've been using Linux for awhile. During our fall competition (OCCRA, it's a local thing, it uses the same controllers though...) we used Ubuntu. Right now we're using a Windows laptop and running Cygwin (the kind benefactors of the free laptop won't let us reformat), a little redundant, but it gets the job done. I don't know where we'd be right now without subversion, Windows or Linux, all teams should use it.
For anyone looking for project and resources for Linux programming, head over to:
http://adambots-live.sourceforge.net/
We haven't updated the site since the end of fall, but I'll get on John for that tomorrowish.
Happy Linuxing!