Make it clear that it is meant for critique, not for vapid "nice shot" comments.
Maybe collect a group of respected photographers to comment constructively.
Adding a showcase forum is a good idea. Not everybody wants to risk having his shots pulled to pieces.
Indeed. That's some good stuff, jaapv. Thanks again for the feedback.
I've set up a "Forum rules" block atop that forum that spells it out (as well as in an introductory post in the forum). I like the idea about a "respected photographer" group. Once we get more members, we'll see about setting up such a group as I think that would be great. Anyone care to volunteer to moderate that forum (besides myself)?
I've added a Share a Photo
forum as well, for general sharing without the threat of imminent critique...