We've completely missed a lot of news about this project over the year. Wikipedia has a good summary:
http://en.wikipedia.org/wiki/The_Muppets_(film)
The plot involves:
"The Greatest Muppet Movie of All Time is about Gary, Mary, and Walter (a man, his girlfriend, and the man’s life-long nondescript, brown puppet best friend) getting the old Muppet gang—now retired entertainers known for the same Muppet show we know them from—together to save the TV studio that the original show was shot in. A villain, Tex Richman (nice name, on par with Doc Hopper), bent on drilling for oil underneath the studio, is due to take over the studio in weeks and the only way to stop him? Putting on a show that draws ten million viewers."
It's now simply titled "The Muppets". Jason Segel (How I Met Your Mother) is writing and starring, alongside - as his girlfriend ....Amy Adams! Yes!

Set photos:
http://www.slashfilm.com/set-photos-the ... new-movie/Here is what we know about the movie thus far:
• James Bobin is directing from a script by Jason Segel and Nicholas Stoller.
• The film will be in the tone of the classic Muppet films like The Muppet Movie, The Great Muppet Caper, and Muppets Take Manhattan.
• Jason Segel will play the lead role, a human named Gary, whose best friend is a Walter, a new iPhone-wielding Muppet named Walter voiced by Paul Rudd. The character has been described as “a sweet, slightly naive twenty-something Everypuppet who, in the movie, is the best friend and roommate of Segel’s character, Gary. Both Gary and Walter are die-hard Muppet fans.” Walter has never met other puppets and idealizes Kermit and the Muppets because they’re the only beings he’s seen that are like him. Together they go on a journey with Gary’s girlfriend Mary to defeat the evil Tex Richman, a man who doesn’t find the Muppets funny and thinks he can smell oil beneath their studio.
• Chris Cooper is playing the villain.
• The cast also includes Amy Adams and Rashida Jones (The Office) in the other key human roles.
• There are plenty of celebrity cameos written into the script (including Sean Penn) and Segel apparently got verbal commitments from most of the stars during the writing process. Other cameos rumored to include Eric Stonestreet, John Krasinski, Ed Helms, Lady Gaga, Jack Black, Donald Glover, Jane Lynch, Danny Trejo, Zach Galifianakis as Hobo Jo & Paul Rudd as Walter the Muppet.
• We know that Jane Lynch will be a prison guard and Danny Trejo will play a prisoner.
US release 23 November 2011.