"But wait a second," you say. "What about iLife? Isn't that all about amateur content?" Not quite. iLife helps normal people create things that feel professional.
This is the definition of amateur. Notably, you can spot things done in their software, Keynote being a glaring example. It has made a template of what a presentation is supposed to look like on a mac.
See when Jobs gives a keynote using Keynote wearing a black turtleneck, we recognize this signature. When your boss holds a meeting with a presentation in keynote with that same or similarly light faded colour background and bold white text, you recognize this as imitation.
Apple have fantastic engineers and fantastic designers and their products reflect a culture that prides craftsmanship, detail and perfection. But to say the web is amateur is to deny the wealth of originality and expression that spreads from it. Youtube has a direct cam to site, record and upload thing going because it enables people to be expressive. They keyword here is "enable" and it's in their advantage to promote the creating of original content by focusing on the enabling factors.
I think the article addresses the problem in a flawed perspective. Facebook being a good counter example. The problem with Apple is probably better tied with their culture. Apple is not social, and until they socialize they will not know what it takes to enable socializing.
A lot of people here are pointing out that MySpace was the amateur failure of the social web, further getting away from idea that social success == amateur, but let's not forget that MySpace was once, many years ago, "the shit" and only got its pedestal kicked out from under it when other sites offered better enabling factors (read: features) to socialize between friends. Sure, MySpace was fuck ugly, because not everyone's creativity is equal! but to say everyone switched to facebook solely because facebook looked more professional? I don't take that. (eh, i guess it was built better to - damn myspace always had fucking down time - whatever)