I was thinking it would be very useful to have an extended version of 
the EditorFor HTML helper which automatically writes out value data bindings for Knockout JS.

This would be for where the client side view model and the server side view model are the same - I've already autogenerated the client side view model by using ko mapping and getting the viewmodel via AJAX.

Has anyone else attempted something like this, or are there any projects which include something similar to what I'm thinking here?

The advantage of this would be that when refactoring there would be no danger of the data bound values being missed.