And I have to say that I am a bit worried about it.

I love Muppets. One might go so far as to claim it's an obsession. I'm also a fan of musicals though nowhere near to the same extent. I don't usually care for musical episodes though. Some, like the one from Buffy, are done amazingly well. Others are best forgotten. Looking at the preview clip for this week's episode... I hope it's not the latter.