Just a thought for the programmers and such:
if you make a version upgrade that isn't about security, perhaps you would want to hold off a couple of days on triggering this upgrade reminder? It would seem that many of the initial problems people are facing could be resolved quietly in the first couple of days with the more hardcore users, then a build made with the fixes and then trigger the upgrade reminder?
I think it would make for a much more enjoyable upgrade experience for everyone involved.
Also: It might be good to have that upgrade reminder mention that the new upgrade is "URGENT SECURITY UPDATE" or "new features" so that people can react accordingly to the type of upgrade - obviously people should work quickly to put in a security update, but they can take their time on a features only update.