i voted mac for one reason only, user friendly to the max(gotta think about the rest of the world here ya? ) and little to no maintenance and how smooth running it is all the time and very very very little danger of viruses(this of course i base on newer intel x86 macs and OSX or OSX snow leopard). I have always been a pc guy since day one, but gave in and got a macbook pro at the beginning of my college career. Primarily because i am majoring in video editing and I absolutely love Final cut pro and all of its extension, and im a heavy user of Apples logic pro for audio engineering. That said, I Love windows 7 thats on my desktop for gaming. I would have to say though, windows xp black edition or royal edition is my fav OS, due to the unlimited DOS and registry edit options that are not available on newer windows OS. That also said, i really hate APPLE as a company and all that they represent(trying so hard to monopolize and level with everyone, but i also hate how microsoft never seems to get anything to that JUST RIGHT point. Done, 2 cents worth completed.
The linux project is great, every year it gets better and better, yet, i cant say its my fav OS to use, and these days this poll doesnt really matter, because you can run all three OS on one computer if your really wanted to.
