Starting March 1, 2012, Google Friend Connect will not be available for non-Blogger sites. Google will be retiring the service which had helped a lot of webmasters to add social features to their sites just by embedding a few snippet of codes on their sites.
Google Friend Connect is not the only feature that Google will be retiring soon. To learn more about other changes that Google will roll out in the next few weeks or months, you can visit this article: More Spring Cleaning Out of Season.
Alternative
Google encourage affected sites to create a Google+ page and place a Google+ badge on their site so they can bring their community of followers to Google+ and use new features like Circles and Hangouts to keep in touch.