OK, so. Lets get a few facts straight.
the new macs run on intel hardware, that is to say that the hardware is PC compatible. You can also run windows on the new macs natively, if you wanted to. To say that they are PC's, however, is an entirely different matter. You will always be able to define PC in such a way as to compass macs, but you can also define it in such a way that encompasses a calculator, or an abacus. Niether of those are PCs but they are portable, affordable, usable by the average person, fit on a desktop, and make repetative work easier by the means of computation. So do we really need to go there? Is it really necessary for people to say "apples are pcs?" no, not really.
You also miss a key point in the whole apple experience when you do this. The term PC was really made a mass market phenomenon when it became PC COMPATIBLE. That is, when any tom-dick-and-harry with a circuit board and a soldering iron could make pcs or pc hardware. And when every idiot can make something... usually every idiot does...
Apple hardware, on the other hand is cherry picked by apple, and their operating system is designed, extensively tested with. This makes the apple OS on apple hardware extremely stable, and extremely well tested. It doesn't NEED a sticker saying that its compatible with OSX. It was raised next to OSX and cared for by the same loving mother. It just works.
Compared to the "PC" experience where you have thousands of manufacturers making thousands of products, leading to millions of possible hardware combinations which could result in a "PC" which windows has to try and take into account for.... oh wait... windows/microsoft couldn't possibly do that. so they leave it to the manufacturer of that video card, or sound card, or motherboard, or whomever to create "drivers" for their hardware that works with windows. So now not only do you have various levels of competence making your hardware, you have varying levels of competence making the software that talks to your hardware.
So... the hardware could be a problem. and the software could be a problem.
But wait, there's more. Each of these drivers are developed in clean-room environments. Where machines are setup in whatever capacities that the hardware manufacturer deems prudent enough to say "it works" and the foware is tested there before getting rubber stamped as "working" did they test that video card with your motherboard, and how the drivers and software worked together? Probably not...
So there could be a problem with the hardware, the driver, drivers interacting with each other, software interracting with drivers, software interacting with each other. Oh my, I *DO* see a potential for problems here...
but... if you act now... you also get a manufactured computer. Some random company has some team of people putting together parts to make a computer you bring home in a box. How thouroughly did they test that? with your favorite application and games? with your OS of choice? With your particular combination of antivirus and antispiware software? With that new sound card you're thinking of upgrading to?
Yea. Good luck with that.
So I think I've appropriately covered some subtle, and vague differences here in why "a mac" is a significantly different beast than "a pc". So there *is* meat to the argument that mac is a more stable piece of hardware than pc. If we can move on past that point, we find ourselves at the operating system.
You see OSX and windows are completely different animals from an engineering standpoint. We're talking mamal vs reptile... way different.
way back in the day you had CP/M and Unix. ok... maybe I'll skip a bit of this history lesson, but please understand that if you're going to argue the concepts of core os differences and issues with me that you should expect to be talking to someone who knows a great deal more than your average user about the fundamental design concepts of the two than you're likely to meet on a sunday stroll through the park.
The basic differences between Unix derivatives (OSX) and dos derivatives (windows) come down to how software is built for the OS and how the user interacts with it.
For the most part a user interacts with Unix as a user. With no more privileges than are required to affect their own files. That's S.O.P. for Unix. You have to explicitly work to become root. So the effects of a virus or spyware limit themselves to affecting the user, and not the system as a whole. This may seem like a subtle difference but the ramifications are considerable.
Now generally speaking people run windows as super-users. So what a user does affects the entire OS. IT's slightly more complicated than that but fundamentally the idea of "privileges" and "ownership" are loosely-bolted-on afterthoughts for windows. And thus significantly easier to circumvent. Also core pieces of software that are commonly used by windows have their claws deeply and firmly embedded into windows. Which is why internet explorer is such a problem... because its something that SHOULD have been just software, but is so deeply embeded in the OS that it's literally a giant back door waiting to happen that can bypass all of the fundamental security principals that they are trying to apply.
Finally the software is of higher quality for macs than for windows. Not only because better programmers care about it, but because the toolkits upon which the software is built is var more modular, adaptable, maintainable, and seperate from the OS.
And none of this touches on things like registry inefficiencies, security practices, software shipped with the computers by default, or other aspects of the experience.
So if formatting your computer every 3 or 4 months to make it run faster. Fixing it constantly. Worrying alot. Wondering if it will work with your next purchase. And generally dealing with the computer rather than doing the tasks that you bought the computer to reform is what you're looking for... then buy a PC. Get a dell.
But if you're looking for a machine that will run. and keep running, and just never ever quit on you... letting you do what you want... well... consider a mac.
And for one final nail in the coffin. You can buy vmware, parallels, or other "virtualization" products which let you run windows inside them on your desktop along side OSX... the recent versions even support 3d hardware accelleration so you can play games from inside windows from inside osx.
In short... for the love of god.. stop saying that pcs are superior animals just because you like them. macs are validly better machines from the principals to the hardware to the software.