While not the social network that people keep murmuring about under their breaths, Google is introducing a new social layer to their search engine that is a clear response to the popularity of Facebook's "like" buttons all across the web. At launch, the feature is only available on search results, but Google plans on rolling this out to many different Internet objects eventually. The functionality requires you to have a public Google profile, and your +1 ratings will be posted to your profile. Your friends will see these ratings on search results they uncover. The goal here is to allow you to see when your friends, assumed to be trusted sources of recommended websites (in an ideal world that certainly isn't ours), approve a website. That way, when deciding among various search results, you have your friend's recommendations to go by.
This isn't a new idea. Microsoft and Facebook formed a partnership late last year that enabled Facebook friend recommendations to show up in your Bing results (and vice versa), and the Facebook results you'll see on Bing are likely to be much more in depth and robust than what you'll get from your Google friends. Until Google can increase connections between Google profiles, and create something that comes even close to Facebook's Open Graph, this will likely be a novelty. This is likely Google's idea of taking baby steps after trying a few times to jumpstart its social networking clout in one "killer App" (talking to you, Orkut).
A video released by Google can be seen below.