Google are trying another social initiative with the +1 button, which you can place on your website and allow users to ‘+1′ your pages. This from Google
The +1 button is designed to help publisher’s content stand out in search results by giving users the ability to +1 content. The more chances users get to +1 content, the more likely publishers’ URLs are to show up in search results with +1 annotations. This helps users highlight which results are most useful and helps publishers better engage with their audience.