Serialized data in 'forum_parents' is definetley not being calculated properly, I've been having issues with sub forums on my forum which were moved during the rc1, looking in db it the forum_parents looks VERY WRONG, and jumpbox also looks very wrong, yet forum layout in ACP looks right (very different to jumpbox) - Causes display bugs aswell. Only way to fix is to create a new forum, this is a very severe bug, I cant confirm if RC2 has fixed this, going to check, bringing it to attention. I can provide db/admin access temporarily to my forum to show this.