Frankly I don't see what people see in Linux. At work I run a Virtual Linux box as a web server and it does great at that. But as a web server it doesn't need a gui and it runs happily by itself, which is how Linux seems the happiest.
Every once in a while I try a Virtual Linux box just to see how it works, I've tried KDE, Gnome, Fluxbox, Openbox, E17 and none of the Windows managers impressed me as something I'd want as my main OS. The whole this seems designed by geeks for geeks and frankly a waste of time for me.
To be frank, I don't see what people see in windows or os X. But then, we can all choose what we want, and that's pretty much why life is awesome, isn't it ?