I don't think there's going to be a huge draft event. Not because "Lol what brand split hurr hurr", but I think that the rosters will simply be quietly shuffled around over the next few months. We have NXT officially becoming developmental, which means the people regularly appearing on NXT now have to be moved up to RAW or SmackDown to make room for the developmental guys. This might be part of the reason for RAW becoming three hours, so that the NXT/Superstars guys become the (majority of) new SmackDown roster, and the RAW Supershow guys officially become the RAW roster.