Who's who or Who's whom?
I understand the difference between them and when to use each, for the most part. The sentence/phrase that's confusing me is "Who's Who" versus "Who's Whom." Most people seem to say that "who is who" is correct because "is" serves as a linking verb. It's not that I don't agree, it's just that I was taught "who is whom" is correct but don't remember the explanation that was given. Can anyone on the "whom" side of the debate explain to me why whom would be correct?