Blizzard is going to swing the nerf bat and it's going to hit Divine Plea. With the intended changes to mana regeneration mechanics in Patch 3.1, where Spirit will be nerfed to curb mana replenishment in raid scenarios, Paladins stand to be unfazed. Spirit isn't a useful stat for Paladins, so Blizzard is looking into raising the healing penalty that comes with Divine Plea, a spell intended to help Protection and Retribution Paladins recover mana. Even with the 20% healing penalty, Divine Plea gives Paladins such phenomenal mana recovery that they don't think twice about using it. Used in conjunction with Avenging Wrath, the penalty isn't even an issue. See, that's a problem.
Blizzard wants the decision to use Divine Plea to be a tough one for Holy Paladins, not a no-brainer. Needless to say, Retribution Paladins and their 5k mana pool use it every time it's up. But when a Holy Paladin with 20k mana can recover 25% of their mana every minute, it's kind of an obscenity. So Blizzard is going to nerf Divine Plea by raising the healing penalty to 50%. Some people think this won't be enough to stop Holy Paladins from using the spell every time it's up, though. Rohan over at Blessing of Kings thinks the spell should not have a healing penalty but be canceled when the Paladin casts a healing spell.