Maybe not completely unique, but probably still stronger than most other healers. Resto druids (from what I've seen so far) can adjust really well and effectively to a different kind of damage pattern. Granted you might need a second gear set with different stats to be really good at it, but the base is there to support those styles.
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Let me first say that I agree 95% with the list that Tiberria put up. Some additions, should they be made:
Agreed.
Incarnation might have some specific uses for certain mythic+ scenarios where there are hectic moments. An extra cooldown can help a lot. Besides the instant regrowths there is 15% extra healing going out, and there might even be a situational use for instant entangling roots (I'm pretty sure some mythic+ need you to think outside of the box and use more than just your healing skills).
Agreed with most points.L90:
Spring Blossoms - A decent default pick for raids because it's reliable added throughput/HPM. Less valuable in 5 mans, because you probably aren't able to have the entire party in an Efflo. Will be particularly strong on stacked fights, but still strong if only the melee group has Efflo on them.
Inner Peace - Really strong if the timing of mechanics that you need/want a raid CD for line up well with having Tranq every 2 minutes. In raids, take Inner Peace if the timings for Tranq work out that way. Otherwise, stick with Spring Blossoms. A pretty weak 5 man talent, since Tranq (even with the out of raid buff) is still only half as strong in a 5 man per person vs a 20 man raid.
Germination - Mathematically a pretty terrible raid talent, because the extra Rejuv costs the same mana and GCD and doesn't add any throughput (outside of the extra mastery stack) while SB and IP add both HPS and HPM. Might have some situational use if you take Cultivation. The second Rejuv is actually worse than the first Rejuv too because you don't get a 2nd Cultivation stack for having 2 Rejuvs on a target, and don't proc Dreamwalker twice. Probably the default talent in 5 mans, since HPM efficiency is a lesser issue, it synergizes well with Cultivation (i.e. 3 easy hot effects/mastery stacks on every party member), and because the other 2 talents are both pretty meh in a 5 man.
Spring Blossoms is a great talent for raids mostly, as you can easily get 6+ people in your efflos. Could still be good for mythic+ if you have a full melee party, or if mechanics force you to stack up a lot.
Inner Peace is probably mostly a raid talent depending on the actual encounter. Maybe it has some specific uses in mythic+ content, but as Tiberria mentioned I don't feel like the cooldown is strong enough, despite having the 5 man buff, to have a big enough impact. The throughput of SotF>WG>Flourish and then a Tranq on top is amazeballs though.
Germination I agree with most of the things Tiberria mentioned. It also offers some flexibility (something he doesn't quite mention), which can be useful at times. If someone chunks particularly hard (e.g. hit for 95% of his HP) than a single rejuv doesn't cut it even if you had taken cultivation. That second rejuv has a big impact HPS wise; but then again such situations in raids is generally better left over to other healers. Your rejuv(+cult) makes sure he doesn't die, other healers can pick him up further. And if a lot of people are hurt this way WG is still there to save the day.
Germination is really really strong in smaller content though. Basically a situation where you couldn't have used that GCD to apply a normal rejuv, is a situation where germination gains potency(*). That was true in WoD, and with the new mastery it will be even more true. For PvP and a lot of mythic+ this will be a go-to talent.
(*) E.g. in a raid germination doesn't add much throughput, because instead of spending a GCD on germinating someone, you might as well have put a rejuv on a person that didn't have one yet and gained the same net throughput without requiring a talent investment.
Flourish is clear cut winner.L100:
Flourish - The clear default talent in most situations - raiding and 5 mans. It's just a huge amount of extra throughput, especially combined with Wild Growth and Essence of G'Hanir plus saves mana and GCDs.
Stonebark - A decent option if you absolutely need the 30 second reduction to Ironbark's CD to keep a tank alive. That will probably happen sometimes in Mythic+ - probably not that often in raids. If you don't need 1/3 more Ironbark casts, Flourish is far better.
Moment of Clarity - A pretty weak option. You could in theory take it if you're having mana longevity issues to cut back on mana expenditure, but you'd probably save more mana/gain more HPM just getting a decent use out of Flourish and throttling casts if needed. It has some synergy with Abundance, so if for some reason you are playing with Abundance (generally not recommended), it might be somewhat decent. Likely to be a mostly dead talent.
Stonebark will definitely see use in mythic+ content, due to the suffix/affix system. Enraging mobs, bosses that hit 2-4x as hard, those are the things where having a high uptime and cycle of tank cooldowns might be a key component (I wouldn't be surprised if it was a major selling point for resto druids).
I don't think MoC will see much play; particularly because I feel Regrowth feels a lot weaker in pre-patch and legion. But should a fight have significant mana restrictions you could consider this.
However I think Flourish would still win in that case as the extension of your HoTs could grant you the breather you need.
Abundance just doesn't flow well. Not only are HT and Regrowth rather low HPM spells as Tiberria mentioned. It's just a badly though through talent. The regrowth component caps out at 4 rejuv stacks and even in that case doesn't provide you all that much extra "umph". The healing touch requires a lot of effort (6-7 rejuvs to get it to 1.5 sec casts), and doesn't deliver for what is needed.
Blizzard decided that they wanted to ignore every and all feedback on this talent and left it like this. I guess you could take it for some gimmicky stuff or just messing around. But I'd take one of the other two talents for anything serious.
Maybe the abundance talent was taken with tank healing in mind or something. But between life bloom, keeping up 4-7 rejuvs, efflorescence and maybe a wild growth now and then, where do you find the time to cast enough HT and Regrowth to get your money's worth?
So far I prefer Prosperity. Cenarion Ward is great as well, but I like having the double charge as a preference; they give me some added flexibility (without SotF, you can heal up 2 targets fast, or 1 target for a huge chunk). Although for legion content I might opt for Cenarion Ward, since it's a stronger heal, so it can function as somewhat of a Nature's Swiftness.