I think the future of the MVC framework is a better question. It's stuck in the middle of two worlds- huge corporate projects don't use it, and anyone that even thinks about MVC will be more likely to use something like Ruby.
.NET vs Ruby is a whole holy war which I'm not going to get into, but there are a lot of people out there who like to get shit done, and find that .NET (and MVC) works just fine (great even) for that.
Incorrect assumption (source: developer at huge corporation on huge projects)
Point is, there was no huge shift to MVC after it was released. A ton of web projects are still made using WebForms and will continue to be. MVC will continue to be a minority framework.
I think the shift has quietly occurred because everyone wants at least a little AJAX, and everyone wants jQuery, and once you've thrown those in the mix, who wants to do that using WebForms?
Why would you assume that if they can't move to a new architecture, they'll move to a new language and OS?