ORIGINAL: RCadmin
go to settings button.
select MyForums
then click the myforums button in the forums, homepage or the forum button on main nav.
only your forums will show
click new posts and only new posts from your custom my forums appear
I'm not sure this answers the question... at least for me.
On the old RCU, in addition to subscribed forums, there was a separate list of subscribed threads that had replies since your last visit. Does this exist still, and if so, where?