This document provides an overview of new features in ASP.NET MVC 4, including new project templates, support for DotNetOpenAuth for external authentication, bundling and minification for performance improvements, device-based filtering for responsive design, mobile enhancements, asynchronous controller support, and the new ASP.NET Web API framework. It also previews upcoming features planned for the fall 2012 update such as SignalR, Windows Azure Active Directory integration, and the Web Optimization framework.