I am subscribed to many of the forums and like to receive the emails. I setup messaging to send me emails regardless of whether I was online or offline. I have continued to receive the emails; however, now when I go to view messages all of those forum posts are showing up as messages. Besides the inconvenience of having to acknowledge receipt of each message, I am concerned about what this will do to the messages table with all of the data from the forum posts being duplicated in the message and message_read tables.
Here is the behavior that I would expect. Since the message configuration (in my case, http://moodle.org/message/edit.php?id=51473&course=1) indicates that the default email address should be used - if it is empty I would expect that the user profile email address be used. When the forum cron goes to send out the messages, if it sends the message via email, I would expect it to at least mark the message as read (move it from message to message_read). The problem I have with this is that then when I go in to look at my history of communications, say with Helen, I am going to see every forum post that she sent as if it were a message.
I think the log should be a clear enough indication that a particular message was sent to the user perhaps with a URL back to the original forum post. Duplicating the content seems wasteful. I think the message (when pertaining to a forum) should be deleted from messages. This is more consistent with the behavior we had in 1.9.
For now, I am testing to see if I can prevent further cluttering the message box by having a default email (email@example.com); however, feel free to remove for testing purposes. Let me know if there are any questions.
Peace - Anthony