It just occured to me to check my Firefox version string earlier today. To my shock, it said "20050514" .. uh, what? And this was right after a post-update restart.

So I ran 'check for update' several more times, and each time, guess what, it only pulled the delta for the following day's build, not all the deltas up to the latest build. Which means that you could easily fall behind if you don't religiously check for updates everyday.

I was thinking that this would be less severe in a stable version, since updates will be less frequent, but depending on how update checks are triggered, pulling only one update is a very bad idea..

Meanwhile, I'm downgrading to the 'release' builds of Firefox and Thunderbird, 1.5 beta 2.