I honestly don't see why a forum like this WOULDN'T continue, for the simple fact that A) it's centralized, and B) aside from a FB or twitter feed, it provides various direct pipelines to the band.
And speaking of FB/Twitter/etc., their lack of centralization I think is the exact reason a place like this has value. Yeah, those other avenues might provide instant access, but those posts and Tweets get buried hour after hour, day after day, to the point where they become obsolete even hours after the fact.
Here, although a thread might stop being active for a bit, it's always present in terms of the list, and we've all seen threads continue for YEARS, or get picked up after a delay for one reason or another.
It's true, in this day and age of instant access, there is more downtime, where in the days of limited access, there was time to debate, converse, speculate, etc. while waiting for the next newsletter or 'zine article. Now, BOOM, information is there, questions tend to get answered in short order.
But again: the centralization is key. The only other place I believe might be comparable is the reddit sub-forum, and I bet even there, there's overlap with DTF (RIP the old Usenet groups, haha... ah, college).
But as long as the band is active, there's always something to discuss, and the centralized aspect will bring the people in. Hell, therushforum is still active as hell (granted, there's still been activity from the Rush camp in general).
So, I think it's all good here.