Dervish said
It's a really cool idea that depends largely on if people are musicians and if you have means to record and post things. I'm sure you could get it to work with some creative ideas, but I think it's a bit of an uphill battle. I've seen people attempt to do RPs where all the participants would draw little comics for each of their posts, and it was REALLY cool to see unfold, but they don't typically last long because if you think getting writer's block is bad, try adding the pressure of drawing a comic with every panel to it. I hope you get this idea off the ground!
Oooh, dammit, there's an RP that I heard about that took place mostly as mini-comics that went on for a while, but I can't remember the name of it for the life of me. Something with powers fueled by dancing though. But yeah, I imagine it could be very difficult.
Swarley said
Wow, thanks for getting me intrigued in your idea. I feel the best way to do this would probably be in the way of making a jukebox musical. Use pre-existing songs to help express what characters are thinking and feeling (Think Rock of Ages, or Mamma Mia). I feel like as cool as writing your own songs would be, it wouldn't really work just because of the fact that you'd need musical accompaniment and that songwriting is very difficult, especially if it's just lyrics.
Yeah, the songwriting without the music was my biggest concern. I could see something like that working though.