Not really. It's for What's New Since you Were Last Here or you last hit Mark Forums Read. It kinda depends on what type of Forum Read Markup you are using (vboptions > general settings).
I would love to be able to change the whats new tab so that it shows active topics instead of just what I havn't read or whatever, its really frustrating cause you gotta go through your forums again find which thread you want.
Their has to be a way to modify it so it shows the last 50 active topics or even 20 or 30?!