Don't get me wrong here, I have a Mac and an AMD machine sitting right next to each other on my desk. (Actually, the AMD machine is laying on it's side as I attempt to remove a bug that seemed to pop up).
Everything I know about 'puters I learned from working with Macs. I learned enough to be able to build a Windows machine without much help from others. 'puters are 'puters, period.
Now selecting an OS is a different situation! Being a graphic artist by trade, I naturally gravitate to the Mac OS. OS X is a new animal, and takes a lot of getting used to. But I still feel more comfortable with that over Windows 2000 or XP. Every time I install something new on the AMD, I really get worried about an unexpected result from the installation. Rarely do I have that fear installing new software on a Mac. Apple's claim to fame IMHO, is that they're so compatible. Working in a Windows environment at work, I can interact with any Win based machine and my work's NT based servers well as the Outlook mail server. Any file that anyone sends to me, I can open and manipulate. CAD, word processing, photos, spread sheets, and anything else I can think of, (except for one thing, see my last note below). I can also save the manipulated files in a manner that the PC users can still work with them just as if the file had come from another PC.
Apple has always valued innovation over power and speed. Until now. PC Magazine performed their own tests on the new G5, and found the Apple's latest desktop is indeed as fast, if not faster, than a Dell Precision 650 workstation with dual 3.06-GHz Intel Xeon processors. You can see the complete review here;
http://www.pcmag.com/article2/0,4149,1274138,00.asp
Now as I get off of my soap box, I will admit that there is one thing that PC's are better at than Macs, GAMES! Now why do you think I built the AMD machine?