This is great news. You know, tonight, before dinner, I prayed that this set would be announced soon, and the announcement was amde on the night I prayed for the official announcement to be made (I also prayed that Sesame Street: Old School Volume 3 would be announced soon... maybe tomorrow?

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I am so glad that The Muppets on Puppets is included. I don't know if I ever thought of that as a possible bonus feature (I might have after I heard of the season two disc contents). And it's so great that this time the set will be reelased in may instead of august (I wonder if season four will be released before the year ends).
I wonder if The Making of the Muppets will be a straight-forward documentary, or if it will be a mockumentary (as in the Muppets give a behind-the-scenes look at the show from their universe), or if it will be a little of both (many real Muppet documentaries have featured the Muppets being interviewed in character). I wonder if this will be all-new, or if maybe it was produced long ago and we don't know about it until now (just like with The Muppets on the Muppets).
Since Beauregard debuted in season 3, it would be great if he hosted the menus. Or, considering the writers strike, maybe there won't be any video menus.