You've got the Linux losers always shouting the greatness of their OS (which is basically We pretty much do everything Windows does! We're almost as pretty as a Mac! And we don't get attacked by viruses because NO ONE USES US.) Then the Apple cutting-edge form-factor loving technofanatics. And of course the average, nondescript Windows user.
Windows users tend to be the sheep of the computer consumer market. We buy Windows-preloaded PCs due mostly to their prevalence and so-called ease of use, though I have it that Apple is actually the Wii of the OS's, while Windows is, go figure, the 360. But all of this has been discussed ad nauseum.
This article speaks a lot to the sensible reasons that are barring a more massive Apple switchover. I think the author, as a former PC user and current Mac advocate, deals evenhandedly with us PC users (I do prefer PCs, but mostly for gaming reasons.) He deals well with Apple's image oriented marketing campaign (refer to reason 5.) I think at this point Macs are evenly or even better enabled for office-related material; they lower network upkeep rates due to their low profile and hard-shelled(against viruses) nature, prevent corporate gaming (WoW has lost companies an estimated such and such amount, I dunno, I read a figure somewhere that it hampered efficiency,) and perhaps most importantly have an intrinsic focus on synchronization (look at the relationship between an iPod and its "docking station," i.e. a Macbook etc.) A layperson has easy access to the Mac's office functions without the opportunity to mess the machine up. If Mac costs were lowered, or rather, the performance reqs for OSX (a "classic" mode OSX? I dunno, something less image-oriented,) it would probably see widespread office use, rather than staying in its current 'elite' place.
Just something to think about.