Apple is swift. They know their demographic and embrace it to sell computers. Unfortunately, it shows the sad state of American business-ethic and responsibilities. Representing Windows-based PCs, a clean-cut and well-dressed plump version of Bill Gates, and representing Macs is the sarcastic loser, who is considered cool.
So we idealize the slacker? The guy is not clean-cut. His hair hasn't been cut or styled--actually, it's been styled to look unstyled. Hint: if you take a stab at cutting it yourself it will look awful, just like it was styled that way.
He's sarcastic. He hides his ignorance is snappy comebacks. Wow! I'm so unimpressed. I like good sarcasm, but its not good on the commercial. Meanwhile the Windows guy is very book-smart, and would win in the physics bee.
He's artsy-fartsy. Supposedly he likes the Macs audio and video capabilities. Well, yeah, but the Slacker drops out of college after 3 semesters studying engineering because he's discovered booze, pot, and loose women. There's not enough time to be a good musician when you're passed out half the time. The Window's guy is working on his PhD.
He's young. Windows-guy is middle-aged. Everybody knows that younger is "smarter." Actually, the guys a pleasure seeker, so "smarts" won't help since they're not applied.
He's single and freewheeling! Windows guy has a wife, a dog, a kid, and one on-the-way. He's very busy, but he also has a home theater with an HDTV, three cars, insurance, a nice home, an in-ground pool, and has a stock portfolio that will ensure a nice retirement bonus to his 401K. Don't get me wrong, Mac-guy has the same TV, but it's hung on the wall in his room at his parents' house. And he'll pay them back for the TV soon, when he can find work that doesn't involve dropping fries. Luckily, he can commute to his job on his bike.
Bottom line is, these stereotypes boil down to "cool" and "uncool." "Cool" doesn't pay the bills, baby. Besides it's not PC vs. Mac, in reality. It's what software you use and how. Mac is probably a better PC for now, but without Bootcamp, you are limiting your software.