In this question, I received a spot-on one line answer in a comment that referred me to a more extensive answer by someone else to a different question on MathOverflow. I plan to acknowledge David Eppstein for his answer on MathOverflow, and to cite one or more of the papers he referred to in his answer. I'm interested, though, in what people think about acknowledging brief comments, especially since the commenter reposted his comment as an answer in an almost under-protest way.
In this specific situation, if the commenter (Peter Shor) were to say, "Yes please acknowledge me," or, "No, don't," I would move with that, either way, so I'm not that concerned with the specific. Rather, I'd like to hear more generally about people's thoughts on guidelines for citations and acknowledgements, and how you'd like them to relate to use of this site.