There are any number of paradigms to follow when developing a large web application. The beauty of MVC is that it allows a separation of concerns. The controller and any helper objects are the responsibility of the server-side framework teams. The models are responsibility of the server-side application guys. The views are the responsibility of graphic designers and client side coders.

If you're dealing with a small-scale application, then yes, it might be a bit of overkill, but it is still easier to keep your source nice and neat by using MVC.

Cocoa, Swing and Flex are all pretty stellar.