And then Centipede (thanks!) sent us this forum thread in which someone who claims to be a Wowhead moderator says it might be down so they can implement "character profiles and gear wish lists (ala CTProfiles)" that they were supposedly hoping to put up before "the end of the month," which is of course right about now.
So when the site comes back up, maybe we'll see some brand new features to play around with. We'll keep an eye on it and let you know more when we do.
Update: Site's back up intermittently with no apparent changes so far. Your guess is as good as ours what's happening here.