Even after being buffed, i still don't think arcane is very useful in raids. It might be viable in single target dps encounters like nef, but will be pretty much useless in bombdps/movement encounters, i think. And this AE buff won't help bombing at all, if you have to refresh arcane blasts during bombing after just casting 2 AEs.

i'm thinking about heroic here. maloriak heroic also has these adds that put this black goo on the ground everywhere and i can't imagine bombing these with AE.
The main problem about AE bombing for me is the AB buff. The AB buff lasts 6 seconds (it does, doesn't it?) and AE won't consume it. But AE won't refresh it either, i think. So you're doing 2-3 AEs, then cast one AB and so on and i can't see this working. honestly i can't. well maybe i'm missing something but keeping AB stacked to 4 during bombing can be very hard.
as for magmaw heroic i agree with you.

Let's examine the talent for a moment: Improved Arcane Explosion - Spell - World of Warcraft.
Now, the important part of the Arcane Blast tooltip:
Giving a bit of leeway for movement/boss mechanics/lag, that's four Arcane Explosions for every refresh of your AB stacks. Again, most fights with adds pose no threat as long as you don't have aggro, so the threat reduction is vitally important with a PbAoE like Arcane Explosion.

Hi i saw on SimulationCraft that they took Fire Power (2/3) in their template.

Anyone has been testing it?
I was wondering if it was worth it or not...

Thanks a lot.

Actually 2/3 Ignite is just as good (7dps more on 500,000 iterations)

The main reason I play Arcane is due to a notion I can't shake that moving completely freely while casting is just too easy mode, there are even a few normal Boss encounters where I literally auto-followed a healer and maintained regular DPS. Yes I realize that's a silly basis for a decision.

But in playing Arcane I feel like it matches fire in a lion share of the fights. Following the example of a fight by fight breakdown:
In Tot4W I take Rohash a perfect scenario since the tornado's need eyes, and Al'akir is a largely static encounter.
On Magmaw, if he survives to a third expose and I get full burns twice, I make up any difference in AOE with 150k DPS near on for those phases.
For Omnitron what I appreciate more then the added damage and mana is the nature of my damage, spreading dots on Poison Protocol when they spawn one at a time, coupled with not doing full damage until about 6 seconds after an action compared to a <2 second AB, small or single add groups go down faster nor are they being killed before I do damage.
Maloriak is mostly static, and one of those fights where I really don't feel like higher area DPS is a meaningful contribution. Stealing the remedy is 70K or so Free mana. I Counterspell, I would expect fire to do so as well and I get 10% damage to boot. Also if higher AOE is key in any fight CD burning AOE is really not that bad if its so important.
Atramedes... well I do the gongs so... sniff.
Without letting this get too much longer, the last thing that is mentioned previously is "execute" periods. As an example, and this also addresses the general loss of free movement, Ascendant Council gives me my worst numbers, and at the same time it is where Arcane feels Most important, I cannot burn freely since we are controlling the damage done, however my ability to exceed DPS means I can almost singly control and match the twin bosses by Burning as needed without full halts to raid damage. I also find arcane survivability very high, Cauterize aside, my small resistance bonuses coupled with normal buffs plus shields that reward the cooldown's with spell power puts my damage taken meters under the rest of the raid, Granted my healers probably don't notice or care. Then, the end of the fight, "execute" time. I stand still, pop everything (Troll Berserking too) under Bloodlust. and I execute better then any other class can. It is satisfying to crush Cho'Gall, Chimaeron, Maloriak and Al'Akir in their "dangerous" third phases.

We may never get past the notion that Arcane is inferior but with the specific Encounters out now Arcane seems vastly more Boss Effective. Its all about your Tool-kit!

You do not want to play Fire, because it is easier (aka better)? That is a very silly basis for a decision.

Sorry to pick apart your boss list, but in the interest of better public knowledge:

Conclaive - you say Arcane is good on Rohash platform because tornadoes require eyes (??). Why you should not be Arcane for Rohash: a) Deep Freeze is almost a requirement for first heroic kills. b) There is so much movement on that fight in general (Wind Blast, platform/positioning changing) that fire is ideal.

Alakir - you say the fight is static. In P1 you move every few seconds: avoid Cyclone Wall, avoid Blizzard, avoid Lightning (if heroic), run in for Wind Knockback. In P2 you a constantly shuffling back and forth to avoid Cyclones and to stand in AoE healing effects. In P3 you mover every few seconds (altitude, and debuff).

Magmaw - in heroic, fire mages are perfect for soloing every parasite spawn (in my experience, 10man). Arcane is a waste if you have no way to handle the adds. There are multiple targets to kill. Fire can impact a super strong combustion and ignite from Magmaw head to Constructs, in addition to throwing LB's on constructs while killing parasites. There is also very frequent movement. However out of the fights you listed, Magmaw is the encounter where Arcane is the least terrible.

Omnotron - one again, movement everywhere. Kiting slimes, running in for Shadow Conductor, running away for Lightning Conductor. Blastwave and impact'ed dots for poison adds.

Maloriak - most raids have to stop damage on Maloriak at 30% while waiting for the next green phase. The challenge is killing all the Vile Swills and Slaves, while staying alive through red phase. With every person in the raid attempting to interrupt Arcane Storm, I doubt you would get many 10% damage bonuses.

Cauterize is the best talent in the game.

People don't have "notions" that we need to "get past". We don't judge a spec based off predetermined prejudices. A spec is either better or worse than another, for any given fight or raid role. It just so happensthat right now, in this very raiding tier, Fire is better than Arcane in almost every way. The moment Arcane has a use, it's only a respec away.

edit: This post is very outdated and Arcane is clearly superior now that I average ilvls have increased by 30 or so.

Ive went from fire to arcane since my guild is have been missing 3% damage buff lately and we are already heavy on range. So far, it isn't as bad as i expected to be it. We are 6/13 H and just started working on H conclave, here is my experience, Gear is is all 359 with 6-7 372's

-Halfus H: I pretty much tunneled Halfus from 100 to 0 once we burned the first drake. I got decent dps numbers (60k), considering the movement from the fire orbs that are launched.
-Magmaw heroic: Wasn't terrible, i managed 25k dps on a 9:30 kill and it could been much better. Used fireward on cooldown and saved burn phase for the exposed head
-ODS H: I was doing pretty good with the puddles and arcanatron buff, but died to anhilator half fight. Fire might be better here, with the kiting and all whats going on.
-Atremedes H: I managed 18k dps, it was pretty annoying with all the movement, Fire does much better here.
-Chimearon H: Excellent dps, especially if you can stand as close as possible to the stack point
-Maloriak H: Useless, Went fire to AOE the adds better since we stop at 30% like everyone
-Nefarian Normal: I did better than expected, i managed 21k dps maximising my cooldowns and interrupt

As for conclave, like fok said, i was last night on rohash and i was top damage on shield with Ab (4) - > PoM -> Ab (4). Improved blink is excellent to move between platforms, Mage ward gives a nice buff, especially when you time it on roash platform during windblast before jumping, and you will have it back again as soon the cd is back up on nezir.

Arcane isn't as bad as it look once you get good feeling of the fights timing with your guild strat. The 13% buff is going to be really strong if it stays. As for now, its totally viable for 25man raids to have 1 of their mages go arcane, especially if 3% buff is missing. Also 6% less damage taken and mage armor provides better survival that eases healers job

^ It appears there is one governing factor and a secondary governing factor. 1. Lack of need to be mobile, and 2. encounters with separate burst phases. The first appears to be necessary in all cases. Proof for that is Al'Akir. While by intuition one could think there is apportunity for high DPS due to the downtimes between phases - especially if one is dedicated on the ads of the 2nd phase - the result is weak since there is need for constant movement. Arcane blast is simply interrupted.

Ideally, the 'Arcane Encounter' is one that you are both stable in position and there is some downtime for all players to replenish mana. Usually one would need an encounter that whatever happens, it allows the player to stay stable in position even if that happens in portions. But big portions.

I've updated the BiS list that simcraft uses: chardev 8 - WoW Cataclysm

I think it's pretty close to optimum, but if someone can spot any errors or knows of a gearset that sims higher than this one, please let me know.

A note about the Reforging: Because Haste/Crit/Mastery are reasonably close together in value, I've opted to always reforge the highest rating on a Hit-less piece of gear to Hit to get as close to the cap as possible (currently missing 1.37%).

Cauterize allows you to cheese certain boss mechanics, such as heroic 25 Valiona and Theralion's blackouts. Since you will inevitably run out of cooldowns for it and stacking with the raid would wipe everyone out, the person with blackout has to run out and die. Being fire, all you have to do is run out, "die" and activate cauterize and healers can heal you back to full, forgoing the need to battle res or have someone soulstone you. If you ever get 2 consecutive blackouts on you can even iceblock the 2nd, and no other spec in the game can do this.

As for AE requirements that are progression stopping, there's heroic maloriak, at least on 25s, you need the AE power in order to kill black sludges before the next phase.