I am looking to get some input from other users on the benefits of server-side MVC. With the power of many javascript libraries. What good purpose does server-side MVC server
Well, you are still going to need an initial page, which could be served by a server-side MVC engine.
Apart from that, client-MVC + REST could work, but I think in big applications you still have different sections and you need to tie these sections together. This would be possible doing it client-side, but I think it's easier to do that server-side.
For the moment I can see both coexisting happily. You could still do as much as possible on the client-side and through REST, but if something is not possible client-side, you still benefit from the server-side advantages of MVC