I'm trying to think of the venue for posting it, but the concept is there. LJ is a likely candidate.
A weekly-ish (timing is kinda "fuzzy" when it comes to art) spot on Hero/ Villain of the Week.
I'd say starting with comics but not necessarily entirely so. Choosing may rotate or vote or something between the participants.
For example next week would be say: The X-Men's Nightcrawler.
Everyone participating does up an image of Nightcrawler and posts it. How polished you make it is up to you.
We've all seen similar things on LJ and the like re: Bat-Girl and stuff.
It's not a competition (except maybe with ourselves). It's for fun and maybe a little for self-promotion of us all. 90% of it is just for fun and sort of bringing artists together.
Illustrator and Concept Artist