The newest version was released last year, but they have been updating it alot since then. Recently, Google updated the user interface and added several usability improvements.
To me, the most significant improvements in the latest version is the real-time analytics and access to multiple-channel funnels. That provides info on all the channels a customer visited to reach your site (paid searches, affiliates, social networks, display ads, etc.), and not just the last channel they used to get to you.