In Wrath, I took every restoration talent that looked useful and only then looked around in other trees. In Cataclysm, the outside trees are too good to do that. Mana is tight right now, and there are more mana-saving talents outside of restoration than you can take even if you go down to a minimum of 31 points in restoration. Which talents are conceivable to give up if you want to spec this way? Here are my ideas.
Nature's Swiftness. The heal is no longer a life saver, and damage is not as spiky as it used to be. I notice a lot of restoration druids still take this one, but perhaps this is just inertia from Wrath. In Cataclysm, Nature's Swiftness isn't that great.
Nature's Bounty. This talent has two effects. First, it improves regrowth. That's nice, but I find I only cast regrowth nowadays during emergencies and during Clearcast procs. I do okay without it. Second, it gives you a speedy nourish if you have at least three rejuvenates rolling. This makes the talent more tempting, but again, you don't need it on most fights if you plan ahead. The main exception I can think of is Chimaeron, but on that fight I'm finding mana usage manageable even when using regrowth instead of nourish. Note that on this fight, twitch heals are required, but they aren't required all that frequently.
Blessing of the Grove. How can one pass up straight healing? It's a matter of comparison. Each point in this talent adds 2% to rejuvenat's healing, and I find that rejuvenate is around a fourth to a third of total healing. Being generous, each point in this talent yields 0.7% more healing. It's below the rule of thumb that when a talent point only makes the player's spells do that much better, it should have about a 1% improvement. I currently have 1/2 points in Blessing of the grove.
Swift Rejuvenation. If you are good at predicting damage, then this talent isn't very important. If damage isn't spiky, this talent isn't very important. Nonetheless, I have found it too useful to live without. I run a fair number of 5-mans in addition to raids, and people are always playing slack in 5-mans and standing in fire and so on. Further, even in raids, I find my damage prediction isn't perfect. I currently take this talent, but it looks survivable without if you have better damage prediction and raid-mates who are good at avoiding needless damage.
Gift of the Earthmother. The main benefit here is the instant rejuvenate tick, though the lifebloom blooms are a nice touch. I haven't tried running without this talent, but it is three points that several druids are living without. I just find that the instant rejuvenate tick is helpful for making a dpser a little more stable before the hots roll in.