I always use Linux as my desktop - never touched a Mac except for when I use my brother's mbp and I only use windows for gaming. (though to be fair I am considering finally venturing into mac-land and getting a mbp for myself).

An exception to prove your rule: I use Linux on all my desktops and servers. MacBook and iPad for demos and on the road. So yes, for those who watch my demos and presentations, they'd think that OS/X is the way to go.