Thank you, I think that answers one of my questions: notification does not go far beyond indicating that there has been activity. What I’m hoping to do is breathe more life into a community by improving communication, and the more action is required from users the less likely that is to happen. At present we correspond by exchanging emails to group addresses manually compiled in Notepad, with no two people having the same list! A Yahoo group would work much better. At present it looks to me as if people would find the bbpress / buddypress solutions more laborious.
Two things about Yahoo groups: 1. The incoming email gives you all the content, without your having to do a second click and go and find it, and 2. you get emails on all contributions to the group you’ve subscribed to, not just when someone specifically targets you. Those limitations in buddypress look to me like killers, but maybe I haven’t understood everything yet.
I hope not, because full and easy integration of communication into a website would make it such a powerful tool.