Until someone uploads the trailer you can see a fantastic recap here:
http://toughpigs.com/ozteaser.htm
Now that I have a better look it seems Scooter is in charge of who enters, or perhaps the complaint department. Sam has a clip board so perhaps he is the guy at the gate. Scooter obviously has a nice part.
Sweetums, Crazy Harry, and some MTI pirates are the Wicked Witches minions. Hopefully we'll still get Sal as a flying monkey. With Sweetums as a hence man, he has to have some great lines. Especially if you consider that there are only like 6 or 7 of them.
Bunsen and Beaker seem to be magical scientists with what looks like a magic making machine. It also looks like they are updating Bunsen's look with new glasses.
Gonzo apprently shocks the others to wake them up when in the poppy field. I like that WAY BETTER then the snow stuff in the MGM film. That looks like a fun scene.
THe muppets star hunt logo on the bus uses the old muppets logo. My guess is that the movie was made before the new logo was made.
So, this looks FREAKY AWSOME!