Here's some of the Top Guilds in the World respond to this change:  http://www.worldofraids.com/topic/16484-focus-cataclysm-raiding-curse-or-blessing/

This week started off with somewhat of a bomb coming from Blizzard. Nethaera announced that there will be major changes to raiding come Cataclysm. The main change is that they are combining all raid sizes and difficulties into one single lockout. 10-man and 25-man raids will have the same difficulty and share loot drops as well. Gating will be there still, but limited attempts are gone.

Naturally, the news caused a lot of discussion regarding whether this change was a positive or a negative. The question is though, how will this change influence the top guilds and progression raiding?

Huge positive

"This will be a huge positive for our guild. We are all very excited over the changes. New content in general is fun, and knowing we don't have to raid it in 10, 10 heroic and 25 normal is awesome to hear. Finally we can just do 25 heroic and not be completely sick of the content the third week it is out," says Xav, protection warrior and officer in Premonition.

Premonition was the first North American guild to kill the heroic 25-man Lich King, but in the process, a lot of the players felt burned out and unhappy about the heavy raid schedule. In particular Trial of the Crusader, where normal and heroic modes were separated, took its toll on many hardcore raiders. The Cataclysm raiding system seems to be the total opposite.

One of the main concerns about this change is the balance in difficulty between 10-man and 25-man raids. In Wrath of the Lich King, the difficulty level has been far from balanced. While in most cases, the 25-man encounters have been harder, most raiders recall Sartharion with three drakes up and how the 10-man version ended up being tougher than the 25-man one.

"We are sceptical of Blizzard being able to balance 10s and 25s appropriately so they share difficulty. There are so many restrictions, like raid buffs and debuffs, how many healers and tanks to bring, favouring all ranged or all melee for synergy and so on. It will be hard for them to do," Xav thinks.

Up until now, the 25-man raids have been where the greatest status has been at. The true progression races have always taken place in the 25-man raids, and Xav thinks that this is how it will be also come Cataclysm.

"We just have to see how it turns out. While we may do 10 player raids on alts or if for some unlikely reason we can't form a 25 player raid, we are going to stay focused on solely doing 25s. Most, if not all top end guilds will be competing together in the 25-man versions," Xav thinks.

Less work, more game

Xass, guild leader of the the German guild Irae AoD who got the world 8th Lich King kill, agrees that the change seems to be for the better. "Some guys are a little unsure of how the raid size thing will change our guild's raiding experience. But especially our veteran players are happy with the changes. A little quotation from a long time member: Those changes will make WoW feel more like a game and less like work again," he says.

For him, the new system seems to take some of the pressure off progression orientated guilds. During Icecrown Citadel progression, 10-man runs felt mandatory, which took away a lot of the fun of it. However, just like Xav, Xass is sceptical when it comes to balancing 10-mans versus 25-mans. While he doubts they can make it happen, he feels that the world first race could get an interesting twist should they manage.

In such a case, Irae AoD does not rule out the guild doing 10-man content. In fact, Xass is eager to try 10-man raids without overgearing the encounters. "It is hard to tell by now, but I can imagine we will give 10-man raids a shot. In 10-man raids there is much more emphasis on each individual player, so raiding is more intense. If they really balance them right, 10-mans will get a lot more attention, but old habits are hard to overcome, so I doubt 10-man raids will replace 25-mans when it comes to PvE competition," Xass says.

One of Blizzard's mantras has been to bring the player, not the class. While Xass feels they have achieved that to a certain degree, end game Wrath of the Lich King content still favoured raid stacking. He is a bit worried that 10-man raids will run into lineup problems.

"In my opinion, 10-man raids are putting too much emphasis on lineups. Covering all raid buffs is still an issue in 10-mans. In 25-mans there are more tactical variations. Though it will depend a lot on the community. At the moment I can't tell which raid size is going to be the 'progression' raid, though if both formats are equally accepted, we will be doing 25-man raids for more loot," he says.

Sceptical

While Xav and Xass are fairly positive towards the change, Paragon officer Lazeil is not among those who immediately embrace it. In Paragon, reactions were mixed. A minority liked the changes, several disliked it though the majority didn't care. "My main fear is that Blizzard will make 25-man content too easy because balancing 10-mans requires it. And there goes my incentive to play the game," Lazeil says.

For a guild that tops the progression world ranking, balancing issues is something they deal with constantly. Lazeil thinks just balancing something like melee versus ranged in today's content is hard in itself, since some specs will be better in some fights. For cutting edge raids, that means raid stacking is required.

"The hardest encounters can only be beaten with a specific setup which has enough stuff like Aura Masteries, Hands of Protection, ridiculous AoE, good single target dps or whatever. Imagine doing the Malygos achievement with a melee raid when Wrath of the Lich King was new. It would be a hundred times harder than with casters. So it all comes down to whether Blizzard can make hard fights which don't require all those special abilities. Personally, I don't think they can," he admits.

Paragon was one of the guilds that pushed the hardest with alt raids during Icecrown Citadel progression. Running three 25-man ICC raids a week in order to gear up their mains, they managed to get a gear advantage that most likely helped them get the world first heroic Lich King kill.

Alt runs is something Lazeil certainly wouldn't mind getting rid of. After Paragon killed the Lich King, Lazeil hasn't touched his alt at all. Though come Cataclysm, he is preparing to level up several classes. Other players in the guild are looking to gear up three or maybe four characters. So instead of running multiple runs with each characters, they seem to be aiming for the same amount of runs just with several toons. The main reason is that Blizzard is continuing the gating system, which makes top guilds want to farm normal modes with multiple raids both to gear up mains and to have well-geared alts available for class stacking.

"I am guessing most of the guilds that are seriously working on heroic 25-man Lich King wish their resto druids had retribution paladin alts, like one of our druids did. We stacked classes for every hard ICC boss. Six druids on Lady Deathwhisper was nice, for example. Combat rez is so insane. I could easily use 8-10 druids on a fight like Deathwhisper while progressing, and it would still be a good raid. So limited attempts is not the only thing keeping alt raiding alive, but I am glad they are removing those," he says.

Nonetheless, Lazeil doesn't think Paragon as a guild will be affected much. He expects that 25-man raids will keep their status as the main thing, given that Blizzard manages to balance the game properly. And although he is sceptical, he doesn't see it as an all negative thing.

"I guess this is a welcomed change for most of the player base, because most 25-man raiders are stuck in guilds with bad players. 10-mans are more fun for most people. But if I could choose, I would have 25-mans only," he says with a smile.

I guess I'm curious what this does to the main / alt distinction. At first glance it seems plausible that one might be able to support 2 viable toons at a high gear level. But, I suppose that all depends on how much content is available.

It's probably too early to make any final decisions.

It all comes down to how the instances wind up being structured, how much incentive do 25s have, who stays, who jump ships, who steps up, etc, etc.   We shall have to see how this cataclysmic event shakes up the guild!

We have, at the very least, 50 raiders in the guild. I'd like to see everyone's opinions on this.

I would like to change my vote to I want 40 mans back, you know something that feels genuinely Epic! even if it's more difficult to co-ordinate

For those that haven't seen yet:  http://forums.worldofwarcraft.com/thread.html?topicId=24401856405&pageNo=1#0

We're continuing to refine the raid progression paths in Cataclysm, and we'd like to share some of those changes with you today. Please enjoy!

The first of the refinements being made is that we're combining all raid sizes and difficulties into a single lockout. Unlike today, 10- and 25-player modes of a single raid will share the same lockout. You can defeat each raid boss once per week per character. In other words, if you wanted to do both a 10- and 25-person raid in a single week, you’d need to do so on two different characters. Normal versus Heroic mode will be chosen on a per-boss basis in Cataclysm raids, the same way it works in Icecrown Citadel. Obviously the raid lockout change doesn't apply in pure Icecrown terms though, as this change goes hand-in-hand with a few other changes to raid progression in Cataclysm.

We're designing and balancing raids so that the difficulty between 10- and 25-player versions of each difficulty will be as close as possible to each other as we can achieve. That closeness in difficulty also means that we'll have bosses dropping the same items in 10- and 25-player raids of each difficulty. They'll have the same name and same stats; they are in fact the exact same items. Choosing Heroic mode will drop a scaled-up version of those items. Our hope is that players will be able to associate bosses with their loot tables and even associate specific artwork with specific item names to a far greater extent than today.

Dungeon Difficulty and Rewards
10- and 25-player (normal difficulty) -- Very similar to one another in difficulty; drop the exact same items as each other.
10- and 25-player (Heroic difficulty) -- Very similar to one another in difficulty; drop more powerful versions of the normal-difficulty items.

We of course recognize the logistical realities of organizing larger groups of people, so while the loot quality will not change, 25-player versions will drop a higher quantity of loot per player (items, but also badges, and even gold), making it a more efficient route if you're able to gather the people. The raid designers are designing encounters with these changes in mind, and the class designers are making class changes to help make 10-person groups easier to build. Running 25-player raids will be a bit more lucrative, as should be expected, but if for a week or two you need to do 10s because half the guild is away on vacation, you can do that and not suffer a dramatic loss to your ability to get the items you want.

We recognize that very long raids can be a barrier for some players, but we also want to provide enough encounters for the experience to feel epic. For the first few raid tiers, our plan is to provide multiple smaller raids. Instead of one raid with eleven bosses, you might have a five-boss raid as well as a six-boss raid. All of these bosses would drop the same item level gear, but the dungeons themselves being different environments will provide some variety in location and visual style, as well as separate raid lockouts. Think of how you could raid Serpentshrine Cavern and Tempest Keep separately, but you might still want to hit both every week.

We do like how gating bosses over time allows the community to focus on individual encounters instead of just racing to the end boss, so we’re likely to keep that design moving forward. We don't plan to impose attempt limitations again though, except maybe in cases of rare optional bosses (like Algalon). Heroic mode may not be open from day one, but will become available after defeating normal mode perhaps as little as once or twice.

In terms of tuning, we want groups to be able to jump into the first raids pretty quickly, but we also don’t want them to overshadow the Heroic 5-player dungeons and more powerful quest rewards. We’ll be designing the first few raid zones assuming that players have accumulated some blue gear from dungeons, crafted equipment, or quest rewards. In general, we want you and your guild members to participate in and enjoy the level up experience.

We design our raids to be accessible to a broad spectrum of players, so we want groups to be able to make the decision about whether to attempt the normal or Heroic versions of raids pretty quickly. The goal with all of these changes is to make it as much of a choice or effect of circumstance whether you raid as a group of 10 or as a group of 25 as possible. Whether you're a big guild or a small guild the choice won't be dependent on what items drop, but instead on what you enjoy the most.

We realize that with any changes to progression pathways there are going to be questions. We're eagerly awaiting any that we may have left unanswered. To the comments!