According to Financial Times social networking sites are becoming the primary source of information for people these days. That is a sad sad thought that people are willing to believe things said by other people without any attached proof; because let's face it, how many people post links as proof of what they're saying on Facebook?
It'd be foolish to discount Facebook especially as going anywhere anytime soon. Google's Google+ is a sad imitation, and using it in any form seems to limit the person's ability to share things outside of their circle of friends very easily. MySpace has all but disappeared, and you have various other small-time (in comparison to Facebook) networking sites like LinkedIn popping up, so it's obviously something the business world takes seriously. But a news organization it is not.
I like my friends, and love my family, but I don't even believe them when they try to tell me something is fact unless they have something to show as proof. I think there is a weird effect created by these sites that actually makes people believe the majority of their "friends" are really more than just acquaintances. How much do you really know about the people you have marked Friend on facebook? You might know the mundane facts they post about what they ate, where they went over the weekend, how their job is going, etc. but do you really know what kind of a person they are? I can think of several people that act completely different on Facebook than they do in person.
Some may act like a person who can't be fingered for their actions because of a confused sense of anonymity brought about by being online so you're actually getting a more honest impression of them, but just as many act completely differently because it is much easier to lie when you don't have to look someone in the face. There are even some people who view those they interact with online as less than people, almost as if they aren't real, because they don't have to look them in the eye while they're communicating, and these are people you really want to trust as your source of daily information?
My piece of advice on these sites, take what you read and check it through other sources. Find the original source of the information if possible, and form your own opinion. "Trust but verify" should be the number one rule of the internet.