As for the PC is more expensive than Mac's myth, here is an article you should read.
http://www.tomshardware.com/reviews/apple-mac-leopard-windows-vista,1985.html
It isn't that macs cost more than PC, but rather Macintosh does not make cheap computers. The only make mid to high range computers.
@ a12331
A lot of people have the misconception that Macs and Linux are invulnerable to viruses. However, viruses have been made for both. Experience will tell us that no operating system is perfect
@ Anarchyz
I remember hearing about that contest. It is interesting, but doesn't really mean anything. When they hacked the Mac system, they probably took advantage of a certain security vulnerability they new of. Also, one contest does not establish a trend. I am not necessarily saying you are wrong, but it is not enough to establish that Macintosh is easy to hack.
@ NiKKoM
Thanks for re-inforcing my point. Since I do not deal with video and picture editing, I cannot explain why Mac is so good at it, just that most professionals use it.
As for the stability issue, I should narrow down what an operating system is. An operating system is a program that interfaces with the hardware and provides a platform for applications to run on. It also regulates the processing time for applications. Therefore, applications locking up or crashing is often not the fault of the operating system, but rather the fault of the application designer. Also, I don't care if a certain application doesn't work very well right now or that a certain glitch exists. I am looking at Mac vs Win vs Linux as a trend, not at a particular point in time.
Since interfacing with the hardware is such an important job for a Mac, it makes since that it would work better. All Mac computers are built by Macintosh (the individual parts may not be). The drivers are made by Macintosh. The operating system is made by Macintosh. It all works in harmony. In Windows, you can have automatic updates install a Windows driver for a non-windows product and suddenly your computer won't boot windows.
In conclusion, each operating system is good for certain uses. That is why when I work at the computer shop, I have three tech machines: one running Vista, one running Ubuntu, and one running MacOSX.