It does assume that Firefox will become more like Chrome. In fact, the Mozilla foundation has explicitly said they want features that are very similar to what C

It does assume that Firefox will become more like Chrome. In fact, the Mozilla foundation has explicitly said they want features that are very similar to what Chrome offers today. They're working towards a transparent auto-update mechanism, they just shipped a new add-on mechanism in FF5 (http://blog.mozilla.com/addons/2011/06/21/add-on_sdk-builder-_beta/ http://blog.mozilla.com/addons/2011/06/21/add-on_sdk-builder...) that is much like Chrome's and is thus less likely to break on major upgrades, and they have explicitly stated they plan to release major new versions every three months. Just as with Chrome, they're de-emphasizing the major version number. Expect FF6 soon and FF7 before the year's end. Expect the version number to become less meaningful.