Not yet, but it's planned. The AUP integration was really a test for some deeper 3rd party integration we're planning. In a future release (later this year), we're hoping to have a hook system like you mention along with some plugins for JomSocial and others to use those hooks. Things like Commenting, Like'ing, Requests are the starting point, but we're planning more.
Unfortunately, the AUP integration is hard-coded in right now, so you can't just add a plugin to hook into it. You'd need to modify some JFBC code to add stuff to the Activity Stream right now.. however, that's pretty easy if you'd like to know where to start (to point your techie in the right direction)!
Hope that answers your questions, and glad to hear we're on the right track!
Alex