There has been a lot of excitement over Google introducing Social Search as an experimental feature in Labs. Facebook COO Sandberg is also often quoted in this context, saying that “the web is moving from an information economy toward a social economy”. It is clear that both Google and Facebook want to be the platform that brings you relevant search results from people you trust. Who will win this battle?

Let us discount Microsoft and Bing for the moment, as they’re yet to catch up with Google in any case. Marshall Kirkpatrick over at the ReadWriteWeb says no one is the clear winner, but Facebook may have the strongest hand. On the other hand, Robert Scoble says Facebook is the biggest loser in the Twitter search deals.

Among the several factors at play here, such as who has the larger user base, the most important are Relevancy and Recency. Social Search will not be useful unless it is also Real-Time, and Real-Time Search will not be useful unless it is filtered by Social Relevancy.

Today, I follow several people on various social networks, who make up my “social circle”. The problem is not everyone uses the same social network for the same purpose. I follow some people on Google Reader as they share great content there, but I don’t follow them on Twitter, because they tweet mundane stuff I don’t care about. And vice versa.

This is just an example. The point is, a social contact or friend in one network doesn’t necessarily mean that the person is a relevant contact in another network. Today, I have the flexibility of deciding whether a friend is a worthwhile contact to connect on Twitter, Google Reader, YouTube, LinkedIn, Disqus, Digg/StumbleUpon, Goodreads, Last.fm, and so on. Facebook doesn’t give me this flexibility. Making friends on Facebook means I get noise from all the social activity of a contact, much of which may not at all be relevant to me.

Now consider Google Social Search. Because I follow different people in different social networks, Google knows not just who matters to me, but when and in what context. A friend I follow on Goodreads is relevant when I am searching something about books, but irrelevant when I am searching for breaking tech news. Google has the intelligence to apply relevancy to my social search. Facebook doesn’t.

Facebook Groups may try to emulate these different social networks, but I don’t think it likely that they can achieve the rich functionality developed by each of them for specific networks like books, music, etc.

Human beings on earth did not coalesce into one gigantic country, but segregated into multiple countries with their own culture and language. Eric Schmidt says that within five years, the Internet will be dominated by Chinese language content. We humans are social indeed, but not to the extent that we all congregate within one gigantic silo. Social networks on the web ultimately reflect social networks in real life. Google’s platform understands and accepts that, Facebook doesn’t. That’s why Google will not just remain relevant in the “social economy”, it has clear advantages over Facebook in winning the battle.