So a little update.. I tried a normal healing build with Surge of Light in BT (not SWP as expected) and it's even worse than I thought. My dps from it averaged very low dps in the first two thirds of the instance, and that was almost entirely due to CoH crits on trash pulls. During boss fights I could barely use it if at all. Usage was with a tank assist macro, and casting it as often as was reasonably possible.

I must say that using SoL in this way is a major pain in the ass and the talent does more harm than good.

I haven't seen any feedback/requests regarding Surge of Light though on beta forums. It would be good though if it was mentioned at least (since Surge of Light is broken from a dps standpoint also).

Edit: for those not aware of the dps aspect issue of SoL, due to the way it works, at a certain crit rate it will actually decrease dps. This also hasn't been adressed at all in wotlk from what I've seen.

What? No. They have 1 healing tree... we have 2. Which either means their trees are extremely streamlined or they need more talents in one tree since Priests have to spread them in 2.

I'm not demeaning your testing in any way, but commenting that I don't know of any Priest who defended SoL or Searing Light on any level deeper than 'it helps me solo as healer spec' or 'you don't have to take those talents'.

When TBC beta was out I was really excited for SoL because I did a lot of PVP and thought it would be really handy - but back then the free smite damage was not insignificant. I found quickly, though, that the GCD and hassle just wasn't worth it.

It's allright, I wasn't expecting anything from SoL, but I wanted to check again after a year if anything has changed with our "bad" talents. Nothing new though unfortunately. By the way, 28 is off, it was a typo

I'm still surprised though that I haven't seen anyone mention SoL at all on beta forums.. do people simply not care about it?

Changes to raid buff/debuff stacking have been announced, see this post for details: http://elitistjerks.com/871743-post742.html

Here are the changes most relevant to priests for the sake of discussion:

This means Imp. DS won't stack with Totem of Wrath and Demonic Pact, that Focus Magic is now a raid wide buff instead of a debuff and it won't stack also.
Warlocks with a felhunter will be able to provide a slightly inferior spirit buff.
Protection paladins will be able to spec for (a 30 minute duration?) Grace.

Holy priests don't seem to be included in any of the changes, do they need/want to be?
Also I'm guessing more changes to disc will be coming to compensate the new Grace.

Only buff/debuff holy ever provided raid with was Power Word: Fortitude anyway. This change will benefit holy priests in terms of "will I get a raid spot?", since it may open up new spots from "must have" -classes/specs.

Looking at what Buffs and Debuffs Disc/Holy priest has available:

PW:Fortitude: Seems like it only doesnt stack with itself so far. I was expecting it to compete with Bloodpact from a Warlock's Imp. Instead it seems like Bloodpact doesnt stack with a Warrior's Commanding Shout. Perhaps an oversight, perhaps intentional (as 3 specs of Priests bring the same nonstacking buff in PW:F)

Divine Spirit (DS): Doesn't stack with Fel Intelligence (FI) from a Warlock's Fel Hunter. FI gives 3% bonus to Spirit and Intellect, and has a Talent to increase (only mentions) Intellect by 2% more. DS gives 50 spirit, which is matched by FI once you have a base of 1667 Spirit. (1000 if Imp. FI also increases gained spirit by 5%). Seems like DS beats its competitor easily at 70. At 80 DI gives 80 spirit, which is matched by FI once you have a base of 2667 Spirit. (1600 if Imp. FI is 5%). Rumors are we will expect near a doubling of Spirit in WotLK, which would put myself in raidbuffed situations close to 1500 Spirit. If Imp. FI gets 5%, DS may be in trouble.

Imp. Divine Spirit: Doesn't stack with Focus Magic (FM), Flametongue Totem (FT), Totem of Wrath (ToW), Demonic Pact (DP). Yikes. At 70, FM is 80 Spell Power. FT increases Spell Power by 73. ToW increases all Spell Damage by 6% (Doesn't mention healing, so may not apply to us.). Demonic Pact seems to be a debuff put on targets, does not apply to healing. So only FM and FT is relevant to Imp. DS. Imp. DS beats FM at 1334 Spirit, and beats FT at 1217 Spirit. Seems like Imp. DS is in trouble. FM is 150 Spell Power at 80. You would need 2500 Spirit for Imp. DS to beat FM at 80.

Grace: Doesn't stack with Blessing of Sanctuary. Also there is a mention of Grace being 3% damage reduction. At 70 Blessing of Sanctuary reduces damage by 80. In order for Grace to reduce damage by 80, One must be hit for 2667 damage. This makes Grace superior for Bossfights and some 25 man trash. I did not find any new ranks of Sanctuary in WotLK database. For some reason Grace does not need to compete with Paladins' Imp. Devotion Aura nor Druid's Tree of Life Aura, which are both a flat 3% increase in healing received.

I see no mention of Divine Aegis and PW:Shield not being able to stack with Mage Shields.

We already knew that Inspiration and Shaman's Ancestral Fortitude did not stack.

I am thinking that 3% is the single stack. Either he forgot that its been nerfed to 2% or they are increasing it back to 3.

It certainly does not look like impDS will be a major raid buff, as its not too tough to get most of its benefits from other spells.

Here

This seems quite explicit that the total effect is only 3%. I hope that the talent either gets reduced to a 1 pointer or they add something else to it as this is totally not worth specing. I also assume that Blessing of sanctuary will be redeveloped as currently it is applied before armour and basically sucks. We used to think that grace was the single awesome buff that would make disc raid viable but at 3% DR only who would notice it?

It says maximally talented, not maximally stacked. Unless grace stacking was removed and grace is now a flat 3%. Also in the % healing received category we have tree aura and imp devo aura. This means either that the increased healing from grace stacks with tree aura or that it has been removed. Anyhow I just can't see why they would be nerfing grace so much, unless they are planning additional changes to compensate.

Well as they say:
Also they do not have a %increased healing category in that list so I am not hopeful. It could be an oversight but the signs are not good for grace right now. But Beta etc so who knows what they will do.

Having seen how they have worked hard to reduce the requirement of any one spec I wonder if the Shaman's spirit link talent is in for a major revamp because as currently written it looks insanely good and basically a must have in any raid.

Ugh did they seriously add another talent into Discipline without replacing or consolidating anything else?

It's a decent talent but jesus could the tree be any more bloated? I really hope it gets a revision.

Here are the changes I spotted to discipline in the new talents: http://talent.mmo-champion.com/?priest

Unbreakable will: changed to 15% reduced duration
Improved Inner Fire: moved to tier 3, increases effect by 60%
Absolution: moved to tier 4
Enlightenment: increases spell haste by 5% instead of spell power
Focused Power: increases spell power by 4% instead of giving spell hit to smite/mind blast
Reflective Shield: reduced to 3 points, 15/30/45% of damage
Renewed Hope: new tier 8 talent, increases FH/GH/Penance crit chance by 3%/6% on targets affected by Weakened Soul
Grace: sucks
Borrowed Time: changed from 20% to 40%
Penance: 2 second channeling

edit:
Empowered Healing: 40% / 20%

Shadow Weaving: reduced to 3 points
Misery: reduced to 3 points, changed to spell hit
Vampiric Touch: new effect
Pain and Suffering: changed from 60% to 30% reduced damage from sw death

Inner Fire now affects both healing and damage, just checked.

New ranks of Penance
Rank 1(L60): 202/203 damage and 670/756 healing
Rank 2(L70): 224 damage and 805/909 healing
Rank 3(L75): 256 damage and 1278/1442 healing
Rank 4(L80): 288 damage and 1484/1676 healing

Gonna run some tests soon.
edit:
Here are some quick numbers: L76 priest with 1159 spellpower, all disc talents, no holy talents, after a couple dozen casts:
Penance Rank 3 - mana cost 538 - healed anywhere from 1998 to 2165 (3 ticks)
G. Heal Rank 8 - mana cost 1077 - healed anywhere from 5567 to 6142

Confirming that Grace is now 3% reduced damage when fully stacked, no increased healing.

Assuming MMO-Champion is accurate, Grace appears to now be 50/100% chance to apply 1% damage reduction per stack, stacks to 3. The healing increase is completely gone. Between that and it not stacking with Sanctuary, I'm pretty sure PvE discipline is toast at the moment.

New glyphs, from MMO-Champion:
Nothing much to say there, really, although I love the Levitate one. No more farming Harpies!

So it seems you can adjust your Glyphs as needed.

Dear god this. Bloat Bloat Bloat.

Well as Grace is now basically pointless you can drop that for the new talent. Just switch your build to this. one rank of grace gives you a 50% chance of putting the grace effect up on the tank and the second point is 100%. is anyone really going to take this given that we need to invest 18 points into Holy? p.s. MMO champ hasn't updated the earlier ranks of empowered healing but going to 5/5 gives the full 40%/20%

I touched on this earlier when questioning the utility of Pain Suppression by comparing it to whatever you'd need to give up: either a deep Disc talent or Improved Healing. And now with Renewed Hope and the improvement to Borrowed Time, the bottom of the tree has so many good talents it makes the decision of what to cut very difficult. It takes 35 to get to the tier with Rapture, which is where the Bloat really starts, leaving you with 36. Given a potential for 18 in Holy for Improved Healing and 20 (21 with PS) Disc talents available from Rapture and beyond, you're looking at cutting 2 or 3 points.

Improved Healing: affects Penance as well as Gheal (which you probably will cast a decent amount). The real answer as to whether this talent is necessary is if the cost reduction is actually needed. With Rapture and mana batteries everywhere, it might be that this is just a good filler talent for Holy, but completely unnecessary for Discipline.

Grace: If you have Blessing of Sanctuary available, Grace does absolutely nothing. Even without it, the talent's effectiveness has been halved. While it provides Disc with a way of smoothing incoming damage, with a mere 8 second duration it is hard to keep up along with Weakened Soul on more than 2 tanks. As useful as it might be, I wouldn't consider it absolutely necessary.

Aspiration: 20% more Inner Focus and PI is nice, but I'd say the only real reason to take this talent (given the bloat) is the 8 second Penance cooldown. With Penance being improved in the last patch to hopefully be better HPS and HPM than Gheal, I would venture that you'd want to cast it as much as possible. However, if the difference between the two is minor and you're not worried about Grace (either you didn't take it or BoSanc is available) the difference in HPS&M between taking this talent and not would be incredibly minimal.

Renewed Hope, Divine Aegis, Rapture, and Borrowed Time all have good synergies with each other and the rest of the tree (and the points you're taking in Holy). With Penance becoming an extremely powerful and worthwhile spell, I can't imagine cutting it either. For the reasons I stated above, I think a very good place to cut points is from Improved Healing as you just won't need the additional efficiency. If you just go 13 in Holy for Inspiration (don't max Holy Specialization probably) you also have a bit more room to pick up some of the earlier Disc talents you may have skipped in order.

However, the changes to Enlightenment are annoying. While the rundown of the changes suggests that an int bonus was *added*, the 8820 calc on Wowhead shows it adding Int while the 8825 calc on MMO-Champ shows it only increasing Stam and Int. While minimal, it will cut down on crit - an imprtant stat for Disc. Additionally, Spell Haste does not affect cooldowns - the major limiting factor in Disc priest healing. It's possible the 5% haste will be nice combined with gear and other buffs to allow more direct heals to be fit in PWS and Penance CDs, but the discrete nature of its utility instead of the flat 5% healing increase makes it less compelling. I definitely would rather put those poitns in Focused Power (now increasing all dmg/healing) and Improved Inner Fire. Ignoring the talent completely (and mazing the previously mentioned 2) leaves 2 points probably best spent in Absolution but also meaning that dropping down to 13 in Holy really doesn't open up anything useful in Disc since the early to middle parts of the tree now look a bit thin. Thus, perhaps cutting Grace, ignoring PS, and leaving 18 in Holy may be the best option.

Thus, I'm looking at 53/18/-. This build also shows my distaste for Silent Resolve as well, especially in the new Disc style of "spamming" PWS.

With +2k spellpower and 15% pre-talent critical, Penance generates 3893 hps while Greater Heal generates 4403 hps with all the appropriate Discipline talents. Penance heals 695 hppm, while Greater Heal heals 328 hppm disregarding the impact of Rapture. All figures count the Divine Aegis shielding as healing. Due to Divine Fury, Greater Heal will outscale Penance in terms of throughput.

At some point you start to ask yourself whether it's worth it. If you keep PW:S permanently on cooldown (which implies 4 targets), you have quite reasonable regen from Rapture (possibly even exceeding Serendipity/Imp Holy Concentration), but your HPS blows because all you can really do is one Penance or GHeal (or 2x Flash Heal, or if you have a decent amount of haste Penance/Flash Heal). If you delay PW:S so that you don't have a second of dead time every 4 seconds (PW:S/GHeal/GHeal, throwing Penance in on cooldown), your HPS is much closer to that of a holy priest (still not quite there, depending on how much you ascribe to Test of Faith and the Imp Holy Concentration haste bonus), but you're losing out on returns from PW:S and you're still permanently in FSR (unlike a holy priest with 16% clearcast chance). And as far as utility goes, you pick up Pain Suppression (which with rare exceptions is not that useful, although WotLK raid encounters could easily prove me wrong), Imp DS (doesn't stack with a whole shitload of things; regular DS is actually more useful), and Grace, which has had the absolute hell nerfed out of it.

I stand by my earlier statement that PvE discipline is currently toast.

I was looking on new builds for a smite priest right now and I was wondering if some beta-tester could confirm that the "Improved Inner Fire" actually increase the amount of spell power given by the inner fire buff?