KATY PERRY SHOWED OFF HER BOUNCING, HALF-NAKED BREASTS TO ELMO ON "SESAME STREET":

  KATY PERRY filmed a guest appearance on "Sesame Street" . . . in which she sings a cleaned-up version of "Hot N Cold" with Elmo.

  Which would be fine and not very noteworthy, except that Katy was sporting MASSIVE CLEAVAGE

                                                                        (--Here's the clip . . .)

                                                    http://www.youtube.com/watch?v=JXiFsB4SYlc

 And now, the obvious question: Is Katy's outfit appropriate for "Sesame Street"? Without trying to be a prude, I'm gonna go aheaand say NO.

What do you think?