Erich, I replied to your ticket on Trac about this, but thought I’d post my response here as well.
In practice, Forums are for focused discussion. Forum posts are not threaded and you must visit the actual forum post to reply.
Activity updates are freeform and have no real structure, but are threaded and can be replied to without having to visit the actual activity permalink.
However, I’m guessing (like you) that most people will reply to activity comments, instead of the forum topic.
The creation of activity comments have made the forums component somewhat less relevant now.
This is kind of related to a ticket I opened about the usability factor of having too many ways to communicate:
https://trac.buddypress.org/ticket/1419
many thanks for your feedback Ray !
I think the page “textbp.org/forums” does not bring much value to the website. Also for the average user it is difficult to understand what the purpose of that specific page is.
Therefore I suggested a re-design of that specific page:
https://trac.buddypress.org/ticket/1389
Maybe this helps to utilize the forums and also get the user to better understand what is the idea behind a “Group-forum” ?
We are all more or less “living” within the Internet – we are programmers, designers, WP-experts, Professional Bloggers, etc. , but lets put ourselves in the shoes of the average internet-user – would he be able to understand and also use the service which we are trying to offer ?