[rich! @ etiviti]

Taking a forum analogy Groups could be analogous to being the sub forums such as those we have on CSSCreator it is a forum but within that forum we have sub forums labeled ‘Beginners CSS’, ‘Layouts & styling’ etc so these are in fact BP groups and in the forum analogy you do not need to join that sub forum to post to it and as you state you do not need to join BP groups either to post to their forum.

This *Sub-Groups” taxonomy is something I would find useful in BP – (actually would close the door on the whole “normal forums thing”) – group tags is not the perfect solution as I’d like to have inherited properties of the subgroups. Also a support forum while generic is helpful to be disassociated with a group – i think the activity stream, members, etc is too much when a member of a community just wants resolution to an issue with the site, product, whatever-is-being-offered. (my experience is moderating a 500k+ userbase traditional forum with 1k+ subforums arranged in hierarchy state)

but if i can have my cake and eat it too – i think subforums within a group would be the bee’s knees too