I don't know about the interview with the composer, but there was an interview with Piggy and Kermit on the disney motion site and there was a short clip of a new song. KErmit, Fozzie, Gonzo, and Pepe were singing and I think Fozzie had a solo part. So, the muppets aren't being pushed to the side, at least not in that song. Disney is being helpful. They provide lots of money which lets the muppets do a lot of stuff.