What a great idea! I've got a forum I'll be building in the next month or two, and I'm excited at the prospect of using this creativity conduit to get a logo designed (at least for starters).
Once I settle on a domain name (and register it) I'll be posting a contest immediately after.
The thing I'm really excited about is the forum I'm building would be a natural fit for services just like this. So once it gets going I have the hope that we can drive many more folks here.
I look forward to getting to know you!