Source: Google Blog Post
What if while searching on Google, the things what your friends upload, write or share is given preference among the results shown to you. This is exactly what Google has now done with its flagship domain, i.e. Google.com. The results will now include similar entries shared or uploaded by your friends and people who are connected with you through any public services like Twitter, Blogger, Flickr and though I am not sure, I think should be Facebook too!
You can even see the name of your connection (friend) who shared or uploaded the specific entry, so that your eyes immediately focus over the specific results. Google has now even made it easy to connect to more accounts privately using your Google Account, however you can still add them publicly on your Google profile.
[Note: I have included pictures from the Google’s official blog as we still need to wait for the real-time effects till Google completely rolls-out the new features]
A video explains about Google Social search