I just noticed that where user profile pages used to display (something like) "view all questions and answers," they now say "view all questions, answers, and articles" (emph. mine); see the image below, directly beneath the "Top posts" header.
What exactly is an "article" in this context? The relevant link gives a 404 error for each user I've tried. Is this a feature in the process of being added, or something else?
Note that this is only something visible when looking at another user's profile. E.g. if I look at my own profile (while logged in) I see no mention of articles. (This is why in the image below I'm logged out.)