First and foremost, this will be the next tier of raiding. There was some speculation that this would be an interim tier of raiding, however that is not the case. The gear that will come out of the Crusaders' Coliseum appears to be Tier 9.
Secondly, the encounters will be unlocked one per week until all five encounters are available. This mirrors very closely the way the Sunwell Plateau was handled back in Patch 2.4.
Finally, there will be a new "Crusaders' Tribute" mechanic. The mechanic appears to track the number of times you attempt an encounter, and the fewer times it takes you to complete the encounter, the greater the loot will be for the final boss. A type of raid where you are going for the Tribute rewards will be called a "Tribute Run."
For further information about the upcoming patch check out WoW.com's Guide to Patch 3.2.
The full details of the announcement after the break.
This is the official announcement:
In the next major content patch, the construction of the Crusaders' Coliseum on the Argent Tournament grounds will be complete, and it will hold new challenges for players. We'd like to share some details on the new dungeon, which represents the next tier of content for the game, but keep in mind that this is still in development and subject to change. The Crusaders' Coliseum will include:
- New epic 10- and 25-player raid dungeon with five encounters, with each encounter being unlocked one week at a time
- A more intuitive structure for harder encounters. This raid dungeon will have four different versions: 10-player, 25-player, 10-player Heroic, and 25-player Heroic, with each one using a separate lockout.
- Introduction of the Crusaders' Tribute! Each of the Heroic mode instances has a new tribute system that will limit players on the number of attempts they get in the Coliseum each week to present a greater challenge for the most battle-hardened heroes. Additional rewards can be earned depending on the number of attempts left in the tribute run each week when the final boss is defeated.
- New 5-player dungeon with three encounters that will include Champion's Seals as each one is defeated
- New tier of armor and weapons that are modeled with Alliance- or Horde-specific themes
Patch 3.2 will bring about a new 5, 10, and 25 man instance to WoW, and usher in a new 40-man battleground called the Isle of Conquest. WoW.com will have you covered every step of the way, from extensive PTR coverage through the official live release. Check out WoW.com's Guide to Patch 3.2 for all the latest!