Since the days of Google Buzz, the +1 button has been a mystery to users and content producers alike. It’s different from Facebook’s “Like” button, in that it doesn’t directly share content to a user’s social stream. But the cultivation of a social graph has long been the goal of Google, and its connection to search was likely inevitable.
The plot thickened last month when Google launched Search plus Your World. Jack Menzel, director of product management for Google Search, explained that now Google+ users would be able to “search across information that is private and only shared to you, not just the public web.”
For more information go to: http://mashable.com/2012/02/21/google-plus-1-seo/