Due to the state of current American laws and company policies, I believe that Apple computers are currently the best solution in the market [for people like me]. Currently, computers that run Mac OS X and computers that run Windows NT (equivalent to the current Mac OS 10.*) are using the same hardware. That is, ever since Apple switched from PowerPC powered to Intel powered motherboards, they pretty much have the same thing in the cases. The differences?
1. When you buy an Apple computer, you are essentially also paying for being able to sport the Apple brand.
2. The Extensible Firmware Interface
3. Apple's End User License Agreement for Mac OS 10.*
Notice how I did not mention operating system. Since they contain the same hardware, the same software (Operating System) should be able to run on both. However, it can't.
To run Mac OS X on a non-Apple branded computer, you break the EULA. While that is currently in the legal gray-area, Apple has complete right to refuse to provide updates to your operating system, leaving you vulnerable to any security risks that might affect the operating system. What about virtualizing Mac OS X using a professional virtual desktoping software like VMWare? That's great, but Apple will not release anything to help virtualization companies support Mac OS X. This will make Mac OS X support sparse, or shoddy at best. But wait, Windows and Linux runs perfectly in VMWare. Also, VMWare fusion, the mac version, is substantially cheaper than VMWare Workstation, for Windows. That's a price difference of $100, not exactly chump change. What about native installation of Windows and Linux on Apple-branded computers? Well, Boot Camp essentially is a partitioning manager that supports Windows. Linux is not supported. This is due to the Extensible Firmware Interface. Apple computers currently do not have a BIOS like non-Apple branded computers. This makes it very difficult to install native linux, and so your option is Virtualization. Again, this would be substantially cheaper.
Okay, so this leaves the price difference. I think being able to legally obtain updates, have a cheaper way of Virtualization, and access to a lot of proprietary software and toolkits is well worth the extra money.
But will this effect the average user? No. The average computer user probably has never heard of Linux, due to advertising failures. The average computer use has no need for more than one operating system.
Yet for programmers, people who maintain servers, etc. linux is inevitably better. It's not just once that I have trouble programming in Windows. Things just don't seem to work as well. Linux servers just run better (even Windows guys will admit to that). However, you will inevitably need a Windows machine to test your programs on. After all, if you are looking for a consumer base, Windows is where you find it. It still has the greatest share in the Operating System market. Then, if you want to tap into the iPhone/iPod Touch/iPad market, you need a Mac. Even if you just wanted to program for Mac, a test environment is likely needed. After all, you can't just make a freeBSD compatible piece of software and expect it to work on Mac (OS X was based off of freeBSD). Mac OS X has a proprietary Cocoa layer that you have to deal with.