Sure, you can subscribe to a discussion forum's mailing list to keep up with changes, via an email. When you subscribe or monitor a discussion forum, you are notified by an automatic email whenever there is any update to the discussion.
To subscribe to a mailing list: You can subscribe to the discussion forum's mailing list by sending an email to <mailing list name>-project name-subscribe@<domain>.
You must have the "Discussion: view" permission to be made a subscriber. Check with your forum administrator, if you do not have the permission.
As with other items that you may be monitoring, the discussion forum to which you subscribe via an email is also added to the My Workspace > Monitoring > Monitored Objects list. Your user name is added to the "Users Monitoring" list of the discussion forum. Both these entries are removed when you unsubscribe from the mailing list.
To subscribe in digest type, send an email to <mailing list name>-project name-digest-subscribe@<domain>
To unsubscribe from a mailing list: You can unsubscribe to the discussion forum's mailing list by sending an email to <mailing list name>-project name-unsubscribe@<domain>.