I've noticed two things, regarding this and past Muppet movies.
First of all, seems this and the last two came out around the time of the Toy Story movies. Muppet Treasure Island came out a few months after Toy Story, Muppets From Space came out a few months before Toy Story 2, and this next one will come out a year (or perhaps more accuratey a year and a half) after Toy Story 3. Hmm, I wonder if Disney ever considered putting the Palisades Muppet toys or Master Replicas in Toy Story 3....
Secondly, this and the last theatrical film seem to have come out around "end of the world scares". Muppets From Space came out half a year before 2000, when we had the "Y2K scare" (not sure how many of us really took that seriously as an end-of-the-world problem, but I sure was scared). And this movie will come out so close to 2012 (I don't really beleive in the 2012 "end of the wordl" stuff, but at the same time I am scared).