Mods have a new option to add post notices. There are three basic notices currently available but MO specific notices could be added:
citation needed - This post does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.
current event - Post is related to a rapidly changing event.
insufficient explanation - We're looking for long answers that provide some explanation and context. Don't just give a one-line answer: please explain why you're recommending it as a solution. Answers that don't explain anything will be deleted. See Good Subjective, Bad Subjective for more information.
Should post notices be used on MO? If so, when?