Tagging: "poem" or "poems"?

Simple question. For people's original poems posted in ~creative, should they be tagged "poem" or "poems"?

"poetry" is the broader category, and includes discussions about poets and poetry in general. However, when someone posts their poem, should that be tagged "poem" or "poems"?

The tagging guidelines say (or used to say - since I re-organised the Docs pages, I can't find this reference any more) that tags should be plural. That indicates that "poems" is the better tag. But the post contains a single poem, which makes "poem" the better tag.

Opinions?

EDIT: In the end, I went with the popular choice. When I looked at the tags used in ~creative, I found over a hundred topics tagged "poem" and only four topics tagged "poems". It seems that most people naturally choose "poem" when posting a poem, so I standardised the few differently tagged topics to use "poem".