When Google posted earnings this past week, they said that 10,000,000 people had signed up for their +1 "social networking". I had not heard of it so I looked into it. It is apparently like facebook's "like" feature.
Now you will see the +1 icons throughout the forum. I'm not sure of its significance, but I also thought Facebook was going to be a short-term, waste of time fad when it came out.
Here's what it is...
http://www.youtube.com/watch?v=OAyUNI3_V2c