If you're just loading a single page, then yeah - it's pretty useless. If you're spending any time in Topicbox then the benefits of push updates and dynamic preloading pay off, and it's pretty lightweight as Javascript goes.

But yeah, in a perfect world where we had infinite time to develop it, we'd have the backend serve up a non-javascript static version of the content in response to direct links - if nothing else because it makes things a lot nicer for search engines - and then the javascript would load in and take over if enabled to allow you to keep moving through the site like usual.