The Muppets is the 2011 revival of the Muppets property, starring the usual cast of Muppets plus Jason Segel, Amy Adams, Peter Linz, Chris Cooper, and a whole bunch of celebrity cameos.
Walter (voiced by Linz) is a Muppet and the apparently adopted brother of Gary (Segel). They grow up together and Walter feels pretty lost until he discovers The Muppets, whereupon he becomes a lifelong fan. Fast forward to now-ish, and Gary is on the verge of proposing to his longtime sweetheart Mary (Adams), so they're going out to LA, but Walter goes with them to see the Muppet museum.
While there, Walter discovers that an evil businessman aptly named Tex Richman (Cooper) is about to buy the building and demolish it. Saving it would require 10 million dollars, so Walter finds Kermit, they get the Muppets back together, host a show with celebrity input by a kidnapped Jack Black, and everything ends up with a deus ex machina (they fail to fund, but then Richman gets hit on the head and gives them back the building anyway).
So, generally, this is a pretty good Muppet movie. The characters are consistent with their older incarnations, for the most part; Fozzie's "fart shoes" are a little lowbrow for the Muppets, but at least they don't milk that particular goat too much. The celebrity cameos are fun, and there are a bunch of references to the fact that the Muppets aren't exactly close to the zeitgeist. The b-plot (Gary cutting loose from Walter and committing to his relationship with Mary) isn't exactly compelling because Segel is kind of boring next to the Muppets, but Adams is charming as always. I think the movie spends maybe a little too much time on the new characters and not enough with the actual Muppets, but the "get the band back together" goes a long way to establishing them (though not enough time on Rowlf, my favorite Muppet).
The songs are cute, though I'm sad they trimmed Cooper's because it included some backstory. All in all, I think that's too sweet in places, but otherwise a good Muppet movie.
My Grade: B+
Rewatch value: Medium-high
Next up: The Muppets Take Manhattan