Have any postings to stackexchange been cited in scholarly publications?
If one does that, should one just name the author, the subject line, the date of posting, and the URL?
Though this has been posted in the comments, it deserves to be more prominently featured: We have a built-in feature to suggest citation formats.
I think the discussion on MO is perhaps the best place to look. In particular, that thread led to a 'cite' button appearing on each MO post, providing a sample citation, BibTex, and amsrefs.
For example, on this thread, which looks like:
the 'cite' link produces the following for BibTeX:
and the following for amsrefs:
Between the sample citations and the bib/ams refs, I can't think of what else you would want. I suspect that this hasn't been added in on MSE because we aren't research-focused.