In this day an age it's not easy keeping up with what your friends are doing and between blogs, social sites and forums, you'll most likely miss something that would have been of interest. Trying to help you be friend informed without much hassle, Google has released via its Labs an experiment called Google Social Search.
Once activated, Social Search will personalize your search results so that, if there's relevant web content written by people in your social circle, it will be listed at the bottom of the result page under a section called "Results from people in your social circle." The social circle can include Gmail contacts and chat friends, people from groups you are part of, as well as individuals connected via social sites like Twitter and FriendFeed.
According to the Google Blog - "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."
For a bit more explaining on how Google Social Search works see this video below:
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