This is technically a dupe, but the other one doesn't have the set-up, or Miss Piggy's timeless line, "Yes, my love?" nor her confession to the pig to her right, "I love him." Which for me really makes the joke.
This is apparently the sketch that made Frank Oz and Jim Henson reconsider Miss Piggy as something besides a throw away Muppet character. "We saw a lot of possibilities of a love-sick pig." I don't agree, but this is that joke at its finest.
There is so much wonderful puppetry in this, with the way the characters are all reacting to the goings-on and the like. Little things like the frogs looking at each other when Piggy shoves her way past them. Such attention to the performance is what makes the Muppets a cut above other puppet shows.