As long as NW does not announce changes, then this could be a non-event for those CO Platinums like my wife and I who choose to fly NW for its superior availability of upgrades.
One change I would not be surprised to see them make is the elimination of their agreement with Qantas, or at least a substantial (2X ?) increase in the miles required. If CO wants 150,000 RT in BF to HNL, then it does not make a lot of sense to maintain the 135,000 RT FC QF award (I recently procured one of these in F all the way from JFK to MEL/SYD next year).