Interesting arguments even if some of them are a bit wrong. Some of his criticisms about the GUI are legit; I've had similar ones since switching from Linux to OS X in 2001.
I'm not an operating system guru, so I cannot comment on the merits of why Apple chose Mach or why they decided to use a BSD instead of Linux. I just asks that it works, and for 99% of the time it does.
Still, if I had a choice, I'm always going to choose OS X over Linux for my home desktop. I still stand by to mantra, "Linux is only free if your time is worth nothing."
Try this on for size:
"Windows is only cheap if your time is worth nothing."