One my favorite specials of all time is Muppet Family Christmas. I think Danny Horn from Tough Pigs made the point best - Sesame Characters are owned by Sesame Workshop, Fraggles are owned by Henson, and Muppets are owned by Disney. It seems like a bad divorce - you get custody of these children, etc etc. I asked how well the companies work together - can Kermit appear on Sesame, etc etc. Craig (I think partly appeasing the Disney people in the audience) said everyone communicates very well, and while it is very challenging, the Jim Henson Legacy works extremely hard to point out that even though we may never see Kermit introduce Emmet Otter again - it's stll Jim's work and we should appreciate the peice overall rather than nitpick at the things that aren't there anymore. But overall he says everyone plays nice.