We don't need to complicate things, whenever such critical updates come
along, the maintainers can post a message here and in the users ml or even
in the forum (somewhere it will be immediately visible). A template for a
message detailing the bodhi-karma process, with links to the relevant page
for each fedora version might come in handy, as a lot of people using
packages from the *-testing repositories are not aware of the update
internals.