@cwebber The only reason !GNUsocial doesn't have #ActivityPub yet is because I have a fulltime job and noone else has been up for the task .]

Though I'm pretty sure it'd still just be the 100% public parts of AP that would be used/promoted, as I'm pretty much convinced there's no such thing as privacy in the social sphere anyway and anyone using "private" communication in an environment like !GNUsocial or #Mastodon is fooled either by the platform, the administrator or other users. (anything accessible via a web browser isn't made for privacy)