I think the biggest fallacy of all of these articles is that people don't seem to give any thought to the fact that they only see updates from a handful of people. The reason why that is, is because FB has algorithms to figure out who you are talking to most of the time, and basically only shows updates form people who you talk to, or people whose profile you have visited. I deduced this by myself over a year ago, and recently I was watching some interviews with Sean Parker and he was actually talking about this.

So it's just like in real life, the way you have good friends with whom you talk a lot, and just friends you talk to every once in a while, FB does the same thing.