Lumpy Burgertushie wrote:an active topic is one that has x number of posts in it
Not for the purposes of that list.
It's to allow you to choose essentially which forums provide topics for the link. It's not dependant on the hot topic threshold. I just checked the one on this site and the top 2 results have one view and no replies. So you can select particular active forums to be part of the output and not necessarily just every topic that's had a reply since you were last here, which is what the new posts link shows.