I've posted a community policy here (including a new disclaimer).
We're not even sure we need something like this, but I think it could be a good idea. Makes things clear and transparant.
We're not sure we've got the policy just right on the first try. Please let us know what you think in the comments on this blog post. We'll accumulate comments for a few weeks, and see how it goes - then review the policy.
Thanks for you your thoughts, and for just being here.