The work in the Expert Group for JSR 371 progresses and here is a small update. A couple of decisions have been made and the most important one is that the JSR will be layered on top of JAX-RS. The decision was made by voting between this and the alternative of layering it on top of the Servlet API.
What this means for you as a developer is that the stuff you are familiar with from JAX-RS is directly transferable to MVC.
I have made a simple sample project at GitHub that I will keep updated as the specification evolves. Please check it out at https://github.com/ivargrimstad/mvc-samples.