These frequent updates are going to kill Firefox and it's partially Google's fault. Basically, Google has managed somehow to coax Firefox developers to rapid release cycle with frequent Chrome updates. But this goes against Firefox users. Why do people use Firefox? Most users claim extensions. What breaks extensions? Frequent updates. Effectively annulling the most compelling reason to use Firefox. This is certainly…
Haven't had any of my 15 extensions break in 20 releases. I don't expect any breakage any time.
The reason for rapid release is that they need to get new features out to load stuff properly like google docs, yes.
The main reason to use firefox IMO is that its as fast or faster than others (and has all the features of course) AND has this: http://www.mozilla.org/en-US/about/manifesto/ to tip things on it's favors.
Also, I'm using Australis and its just fine. I switch back to release sometimes and I don't really notice the difference anymore. I do prefer the australis tabs contrast.