Earlier today, Salthem posted updated patch notes on the European WoW site and Teza has reposted them at World of Raids with all the changes highlighted. From my quick scan of the list, it appears that resto druids are getting nerfed, mages' Mana Emeralds as well as rogues' Hemorrhage ability are receiving some rather neutral changes, and rogues' Shadowstep is getting buffed.
From my understanding, tree druids are currently able to maintain a high level of healing per second through careful upkeep of Lifebloom on their targets. This is due to the fact that a druid can pop all his trinkets to maximize his +healing and then cast the spell. As long as he keeps refreshing the HoT before it "blooms", it will maintain that maximized level of +healing, thus making for a very efficient and powerful spell. As I understand the new patch notes, this will no longer be possible since the incoming Lifeblooms will overwrite the +healing value of the previous ones. I don't play a tree druid, but I'm sure some of my guild mates will be ranting over this in tonight's raid.