Hope you don't mind me saying... ^^;;
I just really want your thread to do real well. I love the idea behind it, but I think your contest topics should be a little more... structured, if you get what I mean.
Like, make the topic change on a certain day, maybe every fourtnight or so. That way, people can't just drop in willy-nilly and post. And maybe you could be a little more specific with your topics.
Like, instead of just saying "what's hidden under ______'s shell", make it,
"what sort of face is hidden under ______'s shell" or "what does ______'s hidden feet look like".
So then people don't just throw random ideas at it.
I hope this helps. ^^;;