Have you used it? After I heard about the changes coming down the line in 41 a week or so back I immediately downloaded it and started configuring it to be my new main browser. The only problem was that it crashed constantly. It's just anecdotal but my personal experience backs up what I've said here.
Well, to give a counter-anecdote: I've been using nightly for years and only experience severe problems maybe a handful times per year, the rest of the time it works fine.
FYI, i have used Aurora/DevEdition almost exclusively (outside of testing) on at least a dozen different Windows and OS X machines ever since the Aurora channel was created and i have never once had a serious problem. Occasionally i find little visual glitches or whatever, but it rarely ever crashes and i never get data loss or anything severe like that.
