All the information that appears as part of Google Social Search is published publicly on the web — you can find it without Social Search if you really want to. What we’ve done is surface that content together in one single place to make your results more relevant. The way we do it is by building a social circle of your friends and contacts using the connections linked from your public Google profile, such as the people you’re following on Twitter or FriendFeed.
In principal, I like it. But I’m increasingly creeped out about how much Skynet Google knows about me. And maybe its because my social network isn’t big enough, but I think that if I wanted to find how my friend Tim felt about sandwiches, I’m not sure that I would Google it. I think I’d just ask him.
For the record, Tim really likes sandwiches. A lot.
via Official Google Blog: Introducing Google Social Search: I finally found my friend’s New York blog!.