You used to be able to read them even without 180/180. Now you can't read them either. I think they were concerned that so many people joined FlyerTalk after the NY Times article that it would be deflected into a political forum and not a travel forum.
You aren't missing that much. I was wondering what I was missing before I had access. One interesting aspect of OMNI is that you get insight into other poster's personalities that you otherwise wouldn't see.