At the recent Web 2.0 Summit, Microsoft announced that their search engine Bing.com had social media search capability (using Twitter and Facebook) and Google replied with details of its "Social Search" option which has been made available on Google Labs.
When you search on Google a section on the bottom of the search results, shows Social
Search results, from content produced by your friends and contacts in blogs, Twitter, Facebook
and other social media sites listed in your Google Profile.
So if you searched for a new camera, as well as seeing results from the manufacturer,
the retailers, and the review sites, you might also find a blog review of it by one of your friends or contacts,
which is an enormously more powerful recommendation.