I was just wondering about this, too. The approach to moderation here is interesting, I think, and I'm eager to see how it pans out, but there are certain aspects of it that have me wondering "is this a feature, or a bug?" I agree that posters shouldn't be able to mod their own posts. Further, it appears I can mod a given post as often as I like, and I think I would prefer that I be able to mod a post only once (though possibly an "undo moderation" option should be available, since I'm clumsy and might click the wrong moderation option).