In six years Facebook has gone from being a social utility for students of a single northeastern US elite university (a sort of directory+community where Harvard students could find and socialize with each other) to a social utility for nearly 400 million people of multiple ages, languages, and walks of life worldwide (FB passed its sixth birthday last Thursday).
My theory is, that fairly spare original design as a utility made it less flexible for individual users but more flexible for users as a whole – in other words for the changes that going from mere hundreds to hundreds of millions would entail. A pretty bare-bones social utility (like Twitter, too, as opposed to MySpace, which was always more of a self-expression tool than a social utility) is simply a person's social network visualized. [If this makes no sense, pls let me know or post your own theory in comments below.] "In its latest redesign, Facebook is playing up applications, games and search," USATODAY reports. That makes sense to me, because apps and games are one way users can customize their FB experience, and search becomes paramount simply because of the challenge of finding someone among 400 million users – but also grows the tension between those concerned about privacy and those who want to be found by old friends and long-lost relatives. For those concerned about privacy, by the way, here's a very handy how-to article: "The Three Facebook [privacy] Settings Every User Should Check Now": the ones concerning who can see what you share (updates, photos, etc.), who can see your personal info, and who can search for and find your FB profile with Web search engines.