The social engagement tracking in Google Analytics is great. Google +1 works by default if you use the +1 Button Creator. However, one needs to do a bit of configuration to get tracking working for other things like Twitter tweets and Facebook likes. The popular WordPress plugins for Addthis and Sharethis use Google Analytics Events for tracking social engagement rather than the newer _trackSocial method. So, for the time being, if you want to get track social engagement with Google Analytics social reports, you’ll need to add your own code. Don’t be alarmed though, it isn’t all that difficult. This step by step guide about Tracking Social Engagement with Google Analytics will get you headed in the right direction.