As of August, Google has completely discontinued all support of of Google Authorship (SEL article). I’m disappointed because it was one of the more interesting experiments in semantic search and also because I have to eat my words. Two years ago I began recommending author markup to all the authors and web sites I work with. But I’m taking back everything I said in this post: Using rel=author tags on blogs to optimize content ownership. The process was too convoluted and because of that too few authors went to the trouble of linking their content to their Google + accounts. Google tried to do the linking programatically, but often failed in bizarre ways, like Giving Truman Capote credit for continuing to write for the NYT even after his death, for example. So that experiment has ended.
But rich snippets and structured data are not dead yet. And in fact, even Google Authorship may not be completely dead and could return in another form using methods not dependent on humans marking up their pages. But structured data for non-author content is still very much in use and Google is still supporting the use of schema.org markup for SERP enhancements. It may be that eventually Google will use Knowledge Graph/Knowledge Vault and other sources to pull this structured data from web content and associate it with search queries — but for now, whatever markup you can add to your pages that will help Google understand what data your site provides can only help. But I wouldn’t recommend making a huge investment in adding this markup, Google obviously hasn’t quite figured out what help they need from webmasters in creating results with structured data.