If you think that view source / semantic markup is a great feature of the Web platform, then this kind of world is a touch worrying, but major apps have been doing this for years.
Once I worked on this project with a lot of contractors from IBM, and they were the ones defining the architecture. They had a very literal approach to MVC. As in, every single link went through a controller. Home link? Ask the controller. About Us link? Ask the controller. I've implemented MVC in C# (back before they had the framework for it, which from what I gather is pretty cool) and had it be useful, don't get me wrong.