I think the movie has only opened in the US and in Mexico. There's a ton of places around the world the movie has yet to open (though I have no idea how popular the characters are outside the US), so talking about world wide box office is kind of ridiculous at this point.
The movie has done about as well as Enchanted, it didn't have a huge budget, I'm sure it has led to increased merchandise sales, it's been really well received by fans and critics, it has a chance to win an Oscar for one of the songs, it's returned the Muppets to the minds of the general public as a movie franchise, the characters have been everywhere from wrestling to kid's shows to SNL, and I'm sure once it's on DVD it will do really well and further build the characters into favorites with the current youth.
I'm pretty sure everyone at Disney would call this a success. It's not Toy Story, but it's still accomplished all they could have realistically hoped for.