As far as I've seen, there's currently no existing add-on for this. I know this was a feature we had until the end of our stay on vBulletin, although I'm not sure if we need it? It's something I haven't felt really hindered by not having in browsing the site since, and I always found being able to tell who was viewing a thread as more pertinent info than who's viewing the forum. Of course, all of that is just me, and I may be the only one who isn't down with it. :b
Just browsing around and found this. I second the comeback of this feature if it's feasible. I really miss it. Forums feel pretty lonely when you don't know how many people are viewing a section.
