Let me begin this post with a large caveat: I am a Windows user. The last time I used a Mac on any regular interval is back in the days of OS 7.x - to give you an indication of how long ago that was, the Mac itself came with a built-in 14.4kbps modem.
That being said, I have a general observations to make. After interacting with OSX on a G5 we have at work, I have fallen in love with the interface of that OS. Smooth, logical, and sexy, yet with a 100% *nix core when you want to get nerdy. Compare that with XP, in which while a command prompt is still technically accesible, it has been removed from the core of the OS and in the process has lost a lot of functionality.
Originally Posted by Tokyo Slim
1: I can build a similarly specced PC for around $300. A black one. White sucks.
Let's clear this point up first. Pricing has not been a selling point on Apple machines for a very, very long time, and even back in the day it was only because of massive discounts given to educational institutions. This is why you saw many schools and their staff('s families) equipped with Macs.
If people are not buying Macs to save money, then, pricing is essentially irrelevant. This leads me to a second point: the public often prefers design to practicality. I'll point here to the domination of the iPod in portable markets - its functionality comes nowhere near many of its competitors and at a more expensive price, but its sex appeal is undeniable. You can buy a player from Creative that will practically give you a happy ending if you would like, but the tradeoff is you might be a little ashamed to show it off in public.
2: Ok Mr. Fantasy land, go buy a Mac CPU or motherboard at the computer store. See ya in a few years when you figure out that you can't. There are no third party CPU's or motherboards, RAM is fine, but you can't upgrade it, only put in MORE, and how many more is limited by your PROPRIETARY motherboard. If I wanted to upgrade to 4GB of PC2-7200 memory from my 1GB of PC-3200 I could do it. I could switch from my AMD processor to an Intel Processor and still run all the same programs and keep my RAM, HD's and optical drives static. Can't do it in a Mac.
Prior to Apple's switch to an x86-based platform, this claim had more legitimacy.
When Apple rolls out the x86 successor to the G5, and if we're talking upgrades we really should stick solely to desktops here, the motherboard and case are pretty much the only proprietary pieces. Even then, because Intel is now the main company behind Apple's primary hardware, the chipset you'll find on the new Macs is probably very similar to what you'll find in a Dell machine.
Beyond that, I'm not convinced there will not be some sort of hack to Apple's low-level firmware to allow switching out processors, if Apple doesn't choose to allow that themselves. These new Macs do not use BIOS in the typical sense, so it's a little more difficult to engineer a workaround, but usually this sort of thing is only a matter of time once the right person gets ahold of the code.
On the subject of RAM upgrades, there is a very shaky premise behind your example. For one, PC-7200 RAM will not have one tiny bit of impact on system performance unless the bus, or paths connecting memory to the processor, runs at that 7.2GBps rate. That simply is not the case. Even the vaunted Athlon64 still goes with PC-3200 memory. Now granted the architecture of the Athlon64 complicates the situation a bit, but the bottom line is the only time you'll find faster memory being utilized is in an overclocked system.
Furthermore, you can
use PC-7200 RAM (if such a standard existed) in a Mac. It will behave the same way as if you put it into a PC, which is to say it will run at the highest clock speed supported by the bus, in this case most likely PC-3200 speeds. When it comes to amounts of RAM, anything over 2gb is overkill for anyone other than graphics/video editors. Also, because Intel has not yet migrated to a 64-bit architecture, its current processors are capable of addressing a maximum of 4 GB of RAM at most. DIMMS now come in 1 GB sizes, and most Intel boards have 4 slots, which would equal 4 GB of possible RAM.
Aside from the motherboard and CPU, all other components in the Mac are governed by the same standards as PCs. PCI-Express cards are cross platform, so video cards are completely upgradeable. As are sound cards via the also-standard PCI slots.