Well, I saw the movie this morning. The first showing I could. And it was great.
Not much from the commercials was cut. There's some things that I think were cut, but I don't know off-hand whether the visuals were there and they just looped the lines (though looped lines could have been taken from deleted scenes, if not recorded for the trailer). I don't think this film has Statler's "no more" comment from an early trailer. And one commercial had Kermit saying "I love you" at the wedding, but I don't recall hearing that line in the movie (the junior novel has Kermit saying that he loves all the Muppets during the wedding scene).
The part with Miss Piggy saying that Kermit's never been more devoted to her and Rizzo agreeing was cut. Somehow it makes sense for that to be cut. With that in, Rizzo's one line that did appear (with him and Robin lementing that the last movie was all about Walter while long-running characters got less) might have made the joke make less sense.
One thing I wonder: It seems Dominic and Constantine get the Muppets celebrating instead of rehearsing. At one point Walter thinks they'll have plenty of time to rehearse, only for the others to party. But why should the bad guys keep them from rehearsing? They pay theaters to sell out, and steal what they want anyway, so it shouldn't really matter to them whether the Muppets are good or not.
After watching this, I don't mind that it's just Fozzie, Walter, and Animal looking for Kermit, with Gonzo not being among them. After all, they're search for and rescuing of Kermit doesn't take up much of the movie.
I was surprised by how there were so many Muppet characters in the Gulag. Mainly because the commercials seemed to avoid showing scenes with Muppet prisoners (Calico was glimpsed in a prison scene in the first trailer, but can barely be spotted). At one point, I saw a furry purple hand sticking out of a cell, without seeing who it is. I wonder who that was. It sorta looked like a Mutation hand, only a bit too small to be one of the Mutations.
I guess the person who thought he saw Brewster on the wall was wrong. He was clearly not in this.
The stuff during the end credits was funny. It reminded me of Sweetums' first scene in Muppet Vision 3D, with Sweetums entering, the black background, and Fozzie being the first character to appear after Sweetums comes in.
I sat through the whole credits. I noticed that in the copyright credit for the use of a Sesame Street clip, it actually said "characters and elements trademark of Sesame Workshop". It could have just noted Sesame Workshop as owner of the clip, since Kermit was the only character in that clip (it wasn't a clip with Kermit and Grover or Kermit and Elmo, for example). And it actually listed a copyright date for that clip (1974).