We are still working on a solution to fix the "number of posts per page" issue in Guilds.
As far as Announcements go, there are two kinds:
the kind that creates a link in your bubble and
the kind that shows a fade-in, fade-out System message in the footer (or just below the navigation if the footer is disabled)
Developers aren't allowed to create the former (only Admin and certain other Gaia Staff) and this type of bug doesn't justify the latter (that's reserved for short-term Database outages and Security issues).
A sticky in the Bug Reports forum will have to do.
At this point, most of the glitched threads seem to be working correctly for all new posts (please continue to post here if this is not the case).
I'm testing a script today which may be able to fix glitched Guilds threads one thread at a time.