Hmm, I doubt there will be any look at the next film, if indeed it is even happening, due to the lack of news of any kind.
I just saw on digitalbits that the dvd's will come with booklets, animation cells, senitype, character sketch-up cards and jim hensons original notes (for the Dark Crystal).
Possibly more. At this point, I don't care if it comes with the original teeth from Jen. What I am most interested in is a good commentary track by frank oz. I know supposedly Brian Froud is on it, and that is interesting and great, but I want someone who was involved day to day on set, with the actors, muppeteers and everyone else. Frank Oz is the closest guy to Jim, and to hear him give us some insight into the film, and the experiences that happened on set would be great. But I guess if they are not going to do it for its 25th anniversary, then we may never see it.