Take a look at your social signals, how many social backlinks? your rel=author implementation works if your authors are really social and linking to their original content through Google+ and optimizing their posts for organic listings.
Social Social Search is the next step in Search Engine Evolution into a Knowledge Engine.
Increase the Social Signals and your traffic will be back to normal if not better. Your Social traffic will increase first, then in the next update your social signals will boost your organic rankings.