The following was posted in the Blizzard forums today and all I can say is "Boooooo". Although I can sort of agree with the Prayer of Mending one due to its use was being exploited. Not happy about the shadow DPS nerf though, as shadow didn't do all that much to begin with.

Prayer of Mending was intended as a heal that bounces around a group of players. However, players were spamming Prayer of Mending repeatedly on a target to ensure that the target was healed every time he was hit. As such, a cooldown was added to this spell.

Shadow Priests were also doing slightly more than intended damage, so there were some minor adjustments made in order to reduce the effectiveness of Shadow Priests.