I realise comedy is supposed to be for the genre, but that's not how it is used de-facto. Of the 11 questions tagged 'comedy', only two are genre-related rather than just general questions about humour.
Although it's barely used (of the 11 questions tagged comedy, only 6 questions appear to be about the genre), I think it makes sense to have separate tags for the genre and for the use of humor.
We should retag the few mistags and beef up the wiki descriptions.
In literary terminology, comedy and humor are two quite distinct things. Comedy is the complement of tragedy in the great division of the arts. There should be a tag of that, even if it is not frequently used. Any tagging system ought to reflect the taxonomy of the field in question, even if no all users are familiar with that taxonomy. A useful information resource needs to be better informed, and more standard in its terminology than its individual users.