I agree – the disconnect between the activity stream commenting and everything else is a huge usability hole. It sucks. At the moment, my only solution is to disable commenting on those activity stream items (which you can with an existing radio button on the options page IIRC). That makes it more confusing for the user but at least we don’t “lose” replies.
@jivany Using Rich’s subplugin for Forum Extras allows Activity Stream replies to forum posts to appear inline with the actual comment in the forum thread. It is excellent as a workaround for this particularly glaring problem, but the fact that it (and all the other tweaks that we have to make) is necessary is in and of itself indicative of the interaction design issues we’re discussing.
