Basically the difference is that a Forum Leader has moderating privileges and/or authorization in a specific forum as opposed to a Moderator, who can moderate in any forum. Having said that, we do assign forums to Moderators but they're encouraged to keep an eye on multiple areas.
Our software doesn't have the ability to label a Forum Leaders as such at the top of the forum, it labels them as "Moderator" which may add to the confusion.
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