Here's a funny piece of Geek Art called Nick Fury's Boy Band (with Black Widow). It was created by artist Berry Presh, and it features The Avengers doing a musical number. I know Joss Whedon is into musicals, but I don't think we'll be seeing one in the upcoming movie. I love how the Hulk is sad he isn't a part of it.
Would you like to see Whedon throw a musical number into The Avengers?