During our recent look at Wrath of the Lich King, Blizzard announced the strategy that it will employ with five-person dungeons and raid-level content.
Similar to The Burning Crusade, all five-person dungeons will have a Heroic mode. Heroic-mode dungeons are max-level versions with improved loot that offer badge rewards which players can use as currency to purchase high-end gear. In addition, Wrath of the Lich King Heroics will have completely separate loot tables than their non-Heroic verions. Badges will be back as some form of token, though it will be a new type of currency and not the currently used Badge of Justice.
All for Ten and Ten for All!
The major announcement is one that should please anyone who doesn't have the means to be a part of an organized raiding guild, but still wants to experience endgame content. All raid dungeons in Wrath of the Lich King will have both 10-person and 25-person versions. So at level 80, every major encounter and every big boss fight can be experienced with a group of 10.
25-person raiding progression is not dependent on 10-person raiding progression. There will be no attunements or keys to obtain, and you won't be locked out of a 25-person instance if you decide to attempt the 10-person version, and vice-versa. 10- and 25-person raids both have their own, independent progression paths, though the encounters should play out very similarly.
This doesn't mean that organized raiding guilds still won't be at the top of the loot pyramid. 25-person raids will earn more, higher-level rewards, in what should be the equivalent of one "tier" of loot quality.
Originally, raids in World of Warcraft such as Molten Core and Blackwing Lair required players to organize large groups of up to 40 players in order to attain any level of success. This proved more difficult than a large segment of the player base could handle, and the more challenging 40-person raids like Naxxramas were left relatively untouched by a great majority of the players.
In The Burning Crusade expansion, the maximum raid size was cut down to 25 players for the Tier 5 and Tier 6 instances: Serpentshrine Cavern, Tempest Keep, Mount Hyjal and Black Temple, as well as the smaller encounters, Gruul's Lair and Magtheridon's Lair. But even encounters at this size weren't quite as accessible to the more casual player base, even after attunements were removed.
Smaller-scale content is king, as evidenced by the game's most popular raid instance, Karazhan. Karazhan is a 10-person raid instance that is commonly cleared in just over two hours. By designing a 10-person raid version of all 25-person dungeons, Blizzard is hoping that more players will be able to experience the encounters, traverse the dungeons, and collect the loot that are the reward for seeking out the endgame.