I actually like Firefox' new update policy as I understand it.
Firefox used to lump a whole bunch of improvements into one release and then wait maybe 6 months to a year for all of the improvements to be completed and tested before issuing an update to FF. Security issues of course were fixed through updates as soon as the fix was complete.
Now Firefox is basically issuing a new release every time a major improvement, many of which are not visible to the user, is completed. IMO this is a far better approach. Along with this Firefox has now changed the install directory to just plain Firefox without a version number. Users get notified when an update is available and just apply it. So far this has worked great for me with respect to Firefox.
I won't go into any more details about it here, but suffice is to say, like I said I like this change in philosophy by Firefox. Why sit around and wait for an improvement six months after it is completed in order to get lumped with other improvements? Clearly if multiple improvements are interrelated that is taken into consideration if they need to be released together.
The above is why Firefox plans to do away with version numbers in the the "About" box though you will be able to find the version number by going to "about:support"