This looks to be a well-put-together implementation of flux. I recently looked over around 20 or so flux libraries to use for a react app I had started, and found only a couple that I liked. I would put this one near the top, but the one I ended up choosing has been great, but no one seems to know about it!

If anyone is interested: https://github.com/kjda/ReactFlux

It's very similar, but I think I like how Actions and subscriptions to actions are handled with it better.