the matched: Adam Featherstone <email@example.com> Rick Alther <firstname.lastname@example.org> The Anarcat <email@example.com> Aaron Mathews <firstname.lastname@example.org> ...
It's already sorted. Look at the email addresses. :) I'm assuming you mean it should be sorted by real name instead of by email address, so changing the summary to state that. If you're okay with it being sorted by email address, resolve this bug WORKSFORME, otherwise we can use this as an RFE... We'll have to hear the arguments on this one and make a decision.
No argument in the last 6 years + sorting on the first name is not very intuitive in most countries (+ people having First Name - Last Name, those having Last Name - First Name, those using a nick only). The realname field in userprefs.cgi doesn't specify how to type your name, so sorting by realname doesn't make much more sense (also, the realname is optional, so it may be blank in some cases!).
Actually, I have often wanted this. The trick is, it's hard to say when. When I'm searching by name, I want the list sorted by name. Otherwise, I want it sorted by email. We could accomplish this by adding a JS link that sorts the list by name instead of by email, just "Sort by Name" underneath or above the match box.