The biggest issue with the mastery for me:
Hots that are already on the target don't get the increased mastery bonus as the target goes lower in hp.

Re-casting hots that are already on ticking on the target is counterintuitive - plus when people are low on hp, a hot is not the first emergency spell that pops into my mind.
I like Fallenangels idea, it's a continuation of the GotEM idea already in place.

Please correct me if I am wrong on anything, but our mastery seems like something that will be avoided. If I understand it correctly the only healing spells it is going to affect are rejuv, LB and regrowth hot. Lets take a look at the 2 main hots: If I stack mastery to 40% and my rejuv ticks for 3000 on 100% health target then if I cast a rejuv on a 20% target it ticks for 3960. Lifebloom ticks for 1200 on full health target then 1584 on 20% target. These numbers are correct yes? That just doesn't seem like a lot of gain. I find it funny that Blizz pushed us towards a more direct healing style then gave us a mastery that only concerns hots and we don't even have a cheap spammable hot.

I don't care what kind of healing model they are implementing in Cata, nobody is going to be leaving players at 20-40% health levels. I understand that people may sit at 70% ish, but leaving them sub 50% is just goofy. How do you possibly make use of this mastery while tank healing? Do I wait until the tank is at 30% health then stack LB and cast rejuv-I hope not cause that is probably gonna end up badly. Our main source of mana regen is tied to LB so we are gonna want to have it stacked from the very start not to mention they gave us a talent that helps to keep it from blooming.

The tools blizz is giving us to raise a low targets health is not hots so I am confused as to why we have this mastery. I am not a number person, but wouldn't avoiding mastery and stacking crit/haste for throughput on ALL of our healing be the way to go? Does anybody know if mastery can be reforged? I am just very confused as to how this stat can be good for us.

Can't hold the stick at both ends, complaining that druids are losing their HoT focus (not this post in particular) and when
mastery or glyphs boost them then "hots are not doing enough of our healing so they boosts are useless".
The mastery is slanted towards raid healing because hots are in general a raid healing tool, and moreso because it procs from low-HP targets. That's not necessarily a bad thing. The same can be said for the resto shaman and disc priest masteries. The paladin mastery OTOH is aimed at tank healing, with only the holy priest mastery being truly the master of all trades (because of the stacking / rolling nature, if that will hold).
The mastery will also affect WG which has the nice effect of ticking quickly. I'm not sure how it interacts with GotEM, but since it is checked on cast then it's not out of the question for it to affect the instant tick from that talent as well.
As for people being at 50% and not 20% - that's fine, it gives a bonus for targets at 50% too. I posted earlier that the linear nature of the mastery seems a bit off but it's not a terrible thing. Consider the following:
1. Druid mastery gives a linear boost of 10% to targets below 50% and a linear decrease of 50% and upwards.
1. Druid mastery gives a linear boost of up to 20% (current implementation).
On targets that are at 50% and higher both are the same, while for targets below it the 2nd one is better. Still ironically the reactions toward the first I suspect would be better.

edit: really what is lacking right now are numbers. Like it or not, "we're not working on the numbers yet" etc, healers are balanced around numbers. If anyone has a link to how much our heals heal for at 85, that would be much appreciated.

I haven't played in beta so I can only offer my opinion based on the PTR and information I have read. As I said in the previous post our mastery is just for hots, which are going to be a much smaller percentage of our heals than before. I am not sure that it is meant as a raid healing bonus. If it was meant as a raid healing bonus how are you supposed to take advantage of that? Blanketing rejuvs and spamming WG is not viable-they are expensive spells. You may find out that Nourish ends up being a main raid healing tool. If mana is the issue and bringing somebody up from 40% health is not a rush you accomplish a lot more for a lot less mana with a nourish or 2 when you can afford the time. Do you even think you are being pushed in the raid healing direction?

The difference between our mastery and the shammy one is pretty big I think. Theirs takes advantage of their direct heals, which are applied at low health levels and will make up the majority of their healing. Maybe it is just me, but having to apply hots on targets at sub 50% health levels to take advantage of our mastery stat seems to be kind of counter-intuitive.

I have reasons to question the validity of some of these results:

1. In the third and fourth charts down, "Calculating drain excluding spirit based regen using non talented mana supplies" and "Calculating drain excluding spirit based regen using talented mana supplies," I see a mana loss per second in the first of 612 and a mana loss for the second of 648. Why would the first be lower? It appears to me the first is calculating mana consumption off the Moonglow value of 1092, which is inconsistent and redundant considering you have "Comparison between Effective loss per second and Moonglow" on that same chart.

2. Since you compare 3 Moonglow and 2 Furor in the last and second to last charts, do you attempt to compare that to 3 Furor and 2 Moonglow? If you're considering which distribution of 5 points is best for mana regen, I would think this comparison is a necessary and valid one.

3. Also, it appears to me you do not calculate the mp5 value of the higher mana pool provided by Furor. Am I correct in this observation? That difference is huge in the value of Furor, which if corrected I guarantee will prove that Furor is far superior to Moonglow as a mana regen talent.

If I notice anything else I'll point it out.

[Edited] Corrected a mistake I made where I suggested (in my first point) that the mana loss per second in the two charts should have been the same. I edited it to correctly reflect that the mana loss per second of the first chart should be higher than it is. Also, I added in point 3.

Considering there are no heroic instances or even raids available yet I would be hesitant to make any judgements regarding spell breakdowns especially given the fact Blizzard have stated numbers are not tweaked/final yet.

Omen of Clarity and Nourish

It seems that if you are casting Nourish, and notice that it will Clearcast, you would almost always want to cancel-cast and spend the proc on something else (Rg, Rj, WG, HT, Remove Corruption, Hurricane, ...), unless the point of Nourish was just to extend Lifebloom.

Nourish is so weak, that even with the wasted time, you'd get more out of casting something else.

Note that premades have 1400ish less spellpower than they should due to the premade weapons not having any +spellpower, which will skew numbers a fair bit compared to people who run some instances and gotten a real weapon.

The scaling seems to be about the same as on lvl 80 druid (have ~3100 SP on PTR, and I'm seeing only bit lower numbers: ~1k less for Nourish, ~300 less for RJ, ~40 less for Efflor).

The mana cost seems really pushing it to the extreme. Could you please provide info about mana regen as well?

Using ttyl's amount-healed numbers, and tooltip spell costs and cast times, no haste, 15% crit, and ignoring Omen and Moonglow, I get the following single-target rotations (in all cases Nourish is cast at least enough to maintain an Lbx3 stack)

Rotation	%BaseMana/Sec	HPS
No+Lbx3	2.8	4980
add Rj	4.7	5820
add SM	4.9	6021
change to HT (except for LB refresh)	12.3	8113
Add Rg/6s	14.4	8910
Replace all HT and SM with Rg-spam	18.3	9506

Notice that going from 6.0k to 9.5k HPS, the mana cost increases by 18.3-4.9 = 13.4% of base mana every second. Spending an extra 1% base mana per second only increases your throughput by about 260 HPS.

This may make temporary healing by DPS, very attractive.

A moonkin's Lbx3 (same stats, Genesis+MSS), tick will average about 1k, and his Nourish+1 averages about 6k (3s cast though). His Nourish+Lifebloom rotation is good for about 2800 HPS.

Suppose there is a ten minute fight where you have mana issues, and there is a 1-minute period where your share of tank healing needs to be 8800 HPS. If you convince a space-chicken to help you out for that minute, your share of healing drops to just 6000 HPS. You save more than 9% base mana per second, so lets call it 540% of base mana, or substantially more than a full mana bar in starting gear.

His total damage done drops by 10% (1 minute of a ten minute fight). He actually saves mana (Starfire burns his mana more than twice as fast as Nourish, and almost every other spell he uses burns mana even faster than Starfire).

To the people stating they don't believe you need 3/3 revitalize -- remember that you want it to proc ASAP after the 6 sec CD is over. Filling out this talent achieves that and should up your mana regen by quite a bit.