With most classes looking at the Primordial Stone system as a DPS loss in Patch 10.0.7, some last minute Primordial Stone hotfixes have been applied, buffing the Stones by up to 25%.
Ion Hazzikostas mentioned in recent interviews that the Primordial Stone system should be an upgrade for everyone. However, this was not currently the case and with recent hotfixes, it seems that Blizzard may be trying to fix that with a 25% increase to many damage procs.