I’d say you’re right about it being biased, but really, it’s not. Once you’ve used a Mac for some time (even just a few months), you’ll realize that Apple REALLY spends a lot of time designing their UI so that it makes the most sense to the end user (obviously they aren’t perfect though).
Just some neat things like Spaces, Hot-corners, Expose, Widgets – alone make the Mac OS worth it. Yes there are some emulations of these for PC’s, but they don’t work as well and aren’t as stable.
I can say a lot of this first hand, as I work with a User Experience and Interface designer at my company, who is well respected in the design community. He spent HOURS designing the tiniest little elements in our iPhone app (like font styles, font sizes, the size of icons, the shape of buttons, you name it). Apple does the same thing, whereas Microsoft just “makes” a button that will work, and “complete the task”.
PC’s can get the job done, but it generally takes longer and increases your blood pressure 