Found Asa's first comment about version numbers.

Followed the Bugzilla link, and found And I quote:
"When a user opens the About window for Firefox, the window should say 
something like "Firefox checked for updates 20 minutes ago, you are 
running the latest release." "

I can't be bothered do log into Bugzilla every time I don't like what's 
going on, Usenet is much easier/faster. So here goes:

Sorry, I _strongly_ disagree. "Check for updates" is there for those who 
want to know, so add the "20 minutes ago" there. For the rest of us, 
knowing the current version number is enough, if we want to know it at 
all. Which we may do, if we're looking for some add-on. But not otherwise.

Ciao,
Wolf K.