I tried this approach and it's clearly attractive, but it also has some disadvantages. I decided to switch back to rendering static HTML in Django (not a Rails guy), with just a little JS on top for now. These are my main reasons:

- Debugging on every browser was quite painful. I tried to support IE7+ as well. If a server-side code works, it works for everyone.

- Frameworks on the client-side are not as developed as the server-side ones. Also I am reluctant to introduce more client-side libraries than necessarily, so I will end up coding a lot of stuff, that I can get for free in Django otherwise.

- The user will need to wait for the JS to load and execute until they see something on the first pageload (at least in my implementation).

- If there is a bug in the JS it's harder to get it logged.