Google Translate is the latest Google service with a new design based on Google+. Since Google Translate's interface is simple, there aren't many changes: a new grey header, updated buttons and drop-downs.
"We're working on a project to bring you a new and improved Google experience, and over the next few months, you'll continue to see more updates to our look and feel. The way people use and experience the web is evolving, and our goal is to give you a more seamless and consistent online experience—one that works no matter which Google product you're using or what device you're using it on," explained Google last month.