I'm pretty sure the majority of digital artwork, both visual & audio, is done on OSX. I have never heard of any major company in this field that had its artists on anything other than OSX. Maybe linux for some render-farms or something, but the artists' primary workstation is macosx. Also, all the major digit-art tools work sooooooo much better under OSX, or even just under Linux. Example, I've used Autodesk's Maya under windows and under Linux 64bit. The exact same machine, dualboot, into Linux to run Maya is like night & day. This simple little kitchen scene[1] was too much for Windows to handle, would freeze up the mouse pointer while trying to rotate around and work on the models. In linux, silky smooth. Also, the audio-production software on mac is superior to anything ever. Avid ProTools, Logic Pro,etc. Imagine the kinds of scenes LucasArts/Pixar/Dreamworks/etc got going on. When you're project starts to get big and require more RAM to keep it all in memory and flowing well; Linux & OSX will beat Windows completely. Now I'm not going to put all the blame on Windows, perhaps AutoDesk and Adobe don't put as much quality work into the Windows versions. And why should they? Really, I see the Windows versions as just gateways for beginners and young people to pirate them and learn.When you get serious and it's your profession, you switch to OSX. Yes, I said it. Any serious digital-artist is on a mac. Good day sir!

1. http://www.youtube.com/watch?v=NNS66CcUJ1o

SIDENOTE: If Adobe made linux-versions of all their stuff, combined with the already-existing linux versions of Maya and 3DSMax, I believe it would be very good for the digital-art industry.