I am a new member and have enjoyed Muppet Central for several months. It's a fantastic resource and the forum messages are heart-felt and can be very addictive. Please forgive some late comments to this thread, which I've been tracking along...
While I'm glad to see the Muppets back in the public eye, I had a hard time enjoying this movie. During the initial telecast, I turned it off after the first several minutes, but after reading so much about it here I decided to buy the tape, which I watched all the way through.
The best formula for integrating Muppets and people has always been for celebrities with familiar personalities to interact with them in a kind of easy-going, "wink-wink" fashion. That goes from early TV appearances to "Sesame Street" and "The Muppet Show" to years of successful talk show interviews. For lesser actors to try and create over-the-top characterizations around Muppet shtick always ends up dripping with flop sweat. You just can't try to compete. This was the major failing of the movie.
As a long-time Muppet fan, I have to say I just don't like the later characters like Pepe, the monkey, and the lounge singer. They seem like pretenders among the original group, especially in this throwback setting. I think most of the new voices were successful, particularly the Frank Oz ones (though it bothered me that Statler was so off).
It's hard for me to lose the awareness that so many of the original Muppeteers are gone. When Jim Henson died, was it a Walt Disney moment or a Charles Schulz moment? More the latter I think, as the creator infused the product so directly. But if the characters had to continue, an honest effort has been made to recreate the magic.
In future I hope the Henson Company reconsiders the usage of actors and finds a better chemistry between the Muppets and any human counterparts. Fun movie, but better things lie ahead.