What A Shame
If the group can't find from within its members someone who's really good at being a devil's advocate, then they're doomed. Too much homogenity is going to lock in too many "non-negotiable" policy positions they mistake for principles. I'm afraid the authors of the site, once they get past the blogosphere learning curve, are going to spend their time refining the details of positions that non-Left voters will reject because of the basic premises.
David Velleman from Left2Right has pleaded that they're still new at this and that their mission is changing, so there's hope that they'll avoid the fate of instituting yet another insular community. But so far the trend does not look good to these conservative eyes. Pity.