Scott Guthrie has announced that Microsoft has just released the Preview 3 build of the ASP.NET MVC framework. He stated that it includes some additional features over April’s interim build, enhancements/refinements, and Visual Studio tool integration and documentation See this post for download links.
In terms of future direction, Guthrie states:
We are starting to feel good about the URL routing and Controller/Action programming model of MVC, and feel that those areas are starting to bake really well. In future preview releases you'll start to see more improvements higher-up the programming model stack in areas like Views (html helpers, validation helpers, etc), AJAX, sub-controllers and site composition, deeper Login, Authentication, Authorization and Caching integration, as well as data scaffolding support.
He also promises a very long tutorial/ into to ASP.NET MVC shortly.