Part of me is starting to wonder if having a time limit on rounds would be a good idea.  Maybe something like, if we don't hear anything for a week after the last GM post, anyone who hasn't said anything forfeits their turn this round?  Nothing too harsh, I don't want to have anyone have to leave the game or something if they just haven't had time to write something, but at least this way we don't have to wait a long time for only a few people?