I think it's important to keep things in perspective.
For one think, the Sideshow/Weta partnership announced significantly more pieces before the films even came out, than Sideshow on their own ever since they acquired the solo licence.
So this licence has never been in the fast lane.
Add to this the ongoing Jackson/New Line feud. This has left the entire LOTR property very much without a caretaker; we do have licencing people over at New Line, but their help has, so far, been the most obvious in the inordinate amounts of time it took to approve such bizarre achievements as the Frodo and GTW PFs. Yes, thank you for that, New Line.
I'm not as optimistic about a possible adaptation of The Hobbit as some around here. It's a lesser work, and it would seem like an attempt by all the concerned parties to capture lighting in a bottle twice, do something financially safe and tried-and-true, instead of boldly trailblazing like they did with LOTR. I'm sure it would be successful, but I don't see it becoming a phenomenon on the scale of LOTR. Especially if they do something ridiculous like splitting it into two parts.
Anyway. Sideshow was never going full-bore into their own LOTR products; New Line seem to have hampered them. I expect this steady trickle to go on for a few years, and then the lines will slowly fizzle out. I just don't see it catching fire ever again.