Often people tell me that social networking is a huge time-sink. Okay, so they use the phrase "waste of time". I explain to them that it's not a waste of time; it just isn't any more efficient than regular F2F networking. F2F networking involves being in the same physical space with an arbitrary collection of real people and introducting yourself.
However, I am beginning to think that is incorrect; that social networking is better at managing and strengthening ties.
Today I had a first-time meeting with Kfir Pravda. I ran into him at a networking event that was publicized on Facebook. IOW, I would not have met him if it weren't for Facebook. The funny thing about that is that over lunch, we discovered that not only do we both work in the same field, we basically know all the same people, live less than 5 kilometers apart, and have even worked at the same company. IOW, eventually, we would have met even with out FB.
So back to the topic. In a room filled with arbitrary people, you are attracted to those who are "like" you in some way (unless you are a very professional networker and force yourself to introduce yourself to people who are unattractive, which I admit to having done.).
In a social networking space, I believe you are even more attracted to people like you. Not that there's anything wrong with that. This means that our social groups are going have multiple ways to connect with one another. It will strengthen the ties within that social group, and we are going to have a better grasp of the group's size and scope.
I see that already with my synagogue. I opened up a Facebook group for us, and it creates a way to remember people's names, and it gives us topics of conversations when we meet up on Saturdays. Even if you don't look into the other person's interests or write on their walls, you at least can joke about their being your Facebook friend.
In theory, I could dramatically extend my network on FB, LinkedIn, Ning, Plaxo, etc., to people I wouldn't normally meet. In fact, that isn't what is happening. Instead, I find am casting the same size net, but getting more of the fish in the vicinity of the net.
Although I encounter people of a wide variety over the social networking sites, it turns out that in fact, I am not really connecting with them. It's pretty much the same as striking up a conversation with the person behind you in the supermarket. Most likely you won't get beyond smalltalk because you don't have much in common.
Where social networking is effective reflects an ongoing icebreaker game. Here is someone you know, or who is in the same social or professional circle, and here is a tool to keep the conversation rolling.