<p>(<em>I suppose I'll turn my comment into an official answer, so that this doesn't get recorded as unanswered.</em>)  </p>

<p>I think the answer is #1.  The name listed is simply the last person to record a change (i.e., added a new answer or edited an existing post).  This is consistent with the way a lot of other pages work in the SE system.  I suspect that there is some code that makes various pages work this way and this behavior is simply inherited rather than having been coded up separately (and deliberately) to behave that way.</p>
