fwiw, React isn't tied to Node: I've used it with Django via PyExecJS (which just uses raw JavaScriptCore).
this technique is called pre-rendering, and yes, I am amazed people don't do it.
"PyExecJS (which just uses raw JavaScriptCore)." this seems pretty slow or can you cache the execution function. (aka you don't have to parse the js multiple times)
Our backend is jvm so we decided on closure, with this on startup we compile our templates on the server and then pass the rendering functions around pumping the data into it to render initial pages. At the same time, we compile the same templates into javascript functions which are included into our app via the closure dependency system to render on the client. This has the advantage of not having to parse and "compile" a template at the point of delivery.
This is why I think react is an excellent library, because it allows anybody to do this and brings this notion into the minds of developers who jump easily on bandwagons.
I also think that the react team are well on their way to building a library which would fair excellently under all sorts of static analysis
We are actively working on more static analysis tools for React: it's certainly one of our major priorities.