I just got around to reading the Tier-12 set bonuses that will be available in Firelands. Here are the bonuses for resto druids:

• 2-part: Your periodic healing from Lifebloom has a 40% chance to restore 1% of your base mana each time it heals a target.
  
• 4-part: Your Swiftmend also heals an injured target within 8 yards for the same amount.
  

The two-part bonus is huge but will not affect gameplay. It will just regenerate mana for us all the time. Just remember to be extra sure to cast a lot of lifebloom in Tree of Life form, but I am already doing that anyway. The two-part bonus means we already graduate from needing to worry about mana in tier 12. Sustainable throughput no longer looks like the most important thing to aim for. I recently made a couple of Nefarion attempts while accidentally wearing moonkin gear, and my regen was lower than normal, but probably still enough to beat the fight. In tier 12, with the higher amounts of int and spirit, I am guessing we no longer have reason to bother reforging secondary stats to spirit. Just take the spirit that comes on the gear, and reforge everything else to haste.

I'm not sure why Blizzard is making this change. I enjoyed having to manage mana usage, and I was hoping it would last for at least one more tier. Instead, Blizzard seems ready to hasten it out of consideration.

The four-part bonus will affect our gameplay. It's going to be interesting trying to swiftmend people who are near other injured people. In practice, I suspect the best I will be able to do is swiftmend people who are in a group--it will be good to be melee in any group I am healing! Basically, this will tip the scales of using the heal on the tank versus using it on a group to trigger efflorescence. With the extra heal on a neighboring player, it will be even more valuable to cast swiftmend on a group.