Macs:
Good: Easy setup, somewhat easy to use. Apple protection plan is great. Hardware is great at the time you buy them, but have the fastest depreciating performance of any laptop as time goes by.
Bad: Overpriced proprietary machines with a not so great software base. Upgrade options are very minimal. Hardware compatibilty is horrible.
PC's with XP =
Good: Highly upgradeable depending on the kind of manufacturer you go to. Largest Software base. Minimal compatibility issues with hardware. Can be custom built if wanted.
Bad: Crashing, viruses.
Contrary to the Mac commercials, comparing the broad range of pc's to a Mac is pretty ignorant. They are mainly comparing the OS's (Microsoft vs OSX). If you buy from a respectable dealer, then PC's are the greater choice if they are properly protected with a firewall and have a good malware/virus detecter.
Macs are suited to mainly Multimedia editing. This has been there function for over 10 years. Anything else a PC would be able to do equal if not extremely better.
And contrary to the OS being more technologically advanced is rubbish at best. The Darwin kernel that Mac uses is a stripped meager cousin of the BSD kernel. Mac ripped off of linux at its finest. 90% of the features that you see in OSX have been in linux way before OS9 came out >.>
Theyve converted to an Intel based platform now, meaning theyve come over to the dark side of PC's. The only difference between them now is purely the Operating System.