Don't worry, this is not going to be another episode of me harping on about the need for screensharing in Flash, and AFCS in particular. But it is about a little discovery I made when working with AFCS (top secret project ;) over the last week or two.
I needed to extend the SharedWhiteBoard component and prevent it from connecting automatically when it was added to the display list. That turned out to be pretty easy, and whilst scrolling through the list of AFCS classes in Eclipse to pick out SharedWhiteBoard I found this:

There are several classes which, judging by their names, have some role to play during a screen share session.
Unfortunately the sources for those classes are not included with the AFCS SDK, instead these are baked into the SWC. The source code that is available however also makes a few loose references to screensharing, and the grouping and managing of screenshare-originated streams.

So who knows, maybe the foundations for screensharing are being laid. One can hope.