You have to understand the intricacies of how Microsoft ran their corporate licensing programs (which is where Apple faltered in the early days) to see how they became so pervasive. People would buy machines for home use that were the same as they were used to using in their jobs. Back then, the cross compatibility between the two platforms flat out sucked, and even far superior OS's for the time like OS2 Warp got buried by Microsoft's marketing machine (I used to have to support ALL those OS's and many more, including Windows NT (workstation and server), VAX/VMS, HP/UX and Solaris so I got a pretty in depth look at all of those OS's). It is what it is, but as it stands today, Apple has flat out eliminated all compatibility issues and truly offers the superior OS and computing experience (not to mention more secure and stable), and with things like Boot Camp and Parallels, enabling you to run Windows on your Mac if you want to, you have a wider selection of software available than a PC can offer you.
Macs are definitely worth a look these days, no matter what someone's personal bias might be.
jag