I see this as more of a "improving the outlook" update. Control flow bindings, Accessing parent bindings etc. are more of making it look nice and easier. I like it as these are the issues which I've faced and is one of the major criticism of Backbone followers.

Steve's vision with Knockout I assume is to be a binding framework rather than a design one (like Backbone). It's just using Knockout alongside Backbone is too much trouble that both libraries are more or less targeting the same audience.