[elliotanderson]

I've done something similar with a Symfony2 application I'm working on, but with a tweak.

The app is basically one big REST endpoint, but it does some header sniffing to handle requests with a "text/html" Content-Type. If it encounters one, the request to the still goes through and returns JSON, but that response is then injected as a preloaded datastore into the template being rendered. This bypasses the whole double load scenario that Twitter once was. Discourse is a great example of this in action, just have a look at the view-source://