I feel very conflicted about this idea.
On the one hand, announcements are in a separate league of their own; with the Stack Exchange platform having to do some extra stretches and bends to get discussions that aren't exactly Q&A to work, it makes some sense that these questions would be treated slightly differently.
On the other hand...this kind of occurrence only really happens when people don't think the announcement or discussion of the announcement are particularly good, or it doesn't survive the surprisingly low barrier it needs to avoid the Roomba in the first place.
So I have to wonder, is this hand wringing over a circumstance which tends to not be an issue? What of the staff making these announcements; knowing the limitations of the system, what are they doing to ensure that their announcement-style questions aren't removed by the system?
(Maybe they do belong on a blog post if they're being pruned by the very system they're meant to be supporting??)