Even though it's incredibly obvious Macs are the inferior operating system mac fanboys will never realise this.
Maybe because they aren't as widely supported.
What if Mac OSX was released for PC? It's free AND updated like every year... FOR FREE. Once more people start getting it it starts to become more supported. Once it's more supported more people will get it and so on. It's almost similar with Sony where not many games are made for it, initially, because of its price, but then once it lowers and more people get it games start coming out all over the place.
Mac OSX will most likely never be released for PC because Mac OSX is designed to work with the Mac computers hardware configuration, that's probably why they run smoother because they are running off predetermined hardware.
IMO, Windows will vanish someday. Mainly because they are focused on a desktop environment. Linux is used widely as it is, they will probably always be used, and Mac is going portable. Mac Book Air is a good example of that, and the iPhone and iPod Touch. People have already done some pretty interesting things with their iPhones and iPod Touches. One guy hacked his iPhone and put Linux on it, another guy was playing WoW on his iPod Touch. Once components get so powerful and so small who will need a desktop anymore?