New Features
Crusaders' Coliseum
The finishing touches have finally been put on this gladiatorial arena and players can now jump in and fight against "formidable Horde and Alliance champaions, ferocious beasts, and Scourge lieutenants." The Argent Crusade trust that the survivors of the 5, 10 and 25 person raids in the Crusaders' Coliseum are worth to travel on and "join the offensive against Icecrown Citadel and end the Lich King's reign of terror."
Isle of Conquest
This tiny island's abundant resources and proximity to Icecrown makes it a valuable base in the war against the Lich King. Horde and Alliance players over level 70 can join in 40-vs-40 siege battles to gain control of each other's keep and kill the commanding general. Along the way, they can take possession of the docks, hangars and workshops around the island to gain access to powerful siege weapons and strategic attacks.
Expanded Argent Tournament
Argent Crusaders have new daily quests and rewards including new banner and tabard, a mounted squire who can run errands and a brand new mount for paladins. The Silver Covenant and Sunreaver factions also have new reward items, mounts and a new pet. Also, it turns out that the Black Knight isn't dead. Huh?
Soulbound Trades
When you loot soulbound items you'll have two hours to trade them with other raid or group members who were also eligible to loot the item. The system works like Item Buy Back but it won't be accessible if you've enchanted or slotted gems in the item.
New Forms
The Druid Cat and Bear forms have new art with five unique color schemes for each form and faction. Better still, the forms will be colored according to the hair and skin coloring of the Night Elves and Tauren.
Battleground XP
Players can now get experience for completing objectives and gaining honor in the Battlegrounds. You can opt in and out of the XP gain by paying a small fee to figures near the Battlemasters in Stormwind or Orgrimmar. Moreover, players who are defending a controlled capture point will gain a 50% bonus to honor from kills.
Dungeon Raids
In addition to various balance and reward changes, Dungeon Raids now allow players to extend instance IDs repeatedly on an individual basis via the social tab. This gives players more flexibility in completing each instance at their own pace.
Items
There are small calibrations to various values here. Most significantly, items that have a cooldown timer will require the player to wait out one full cooldown period after equipping the item before using the ability, so players who like to switch belts in the middle of a fight may find it more trouble than it's worth. On the plus side, mounts can be summoned much more quickly now.
Class and Profession Changes
Blizzard has instituted so many changes to the various classes, that it's impossible to summarize them. The Death Knight has been rebalanced so much that all talent points have been refunded, giving players a chance to respec their characters.
Interface
Loads of changes here as well, but the two that seem the most immediately useful as the double-paned quest log, the SHIFT-enabled item comparisons and vendor prices displayed even when you're not at a vendor.
Bugs
Squashed.
more here
Crusaders' Coliseum
The finishing touches have finally been put on this gladiatorial arena and players can now jump in and fight against "formidable Horde and Alliance champaions, ferocious beasts, and Scourge lieutenants." The Argent Crusade trust that the survivors of the 5, 10 and 25 person raids in the Crusaders' Coliseum are worth to travel on and "join the offensive against Icecrown Citadel and end the Lich King's reign of terror."
Isle of Conquest
This tiny island's abundant resources and proximity to Icecrown makes it a valuable base in the war against the Lich King. Horde and Alliance players over level 70 can join in 40-vs-40 siege battles to gain control of each other's keep and kill the commanding general. Along the way, they can take possession of the docks, hangars and workshops around the island to gain access to powerful siege weapons and strategic attacks.
Expanded Argent Tournament
Argent Crusaders have new daily quests and rewards including new banner and tabard, a mounted squire who can run errands and a brand new mount for paladins. The Silver Covenant and Sunreaver factions also have new reward items, mounts and a new pet. Also, it turns out that the Black Knight isn't dead. Huh?
Soulbound Trades
When you loot soulbound items you'll have two hours to trade them with other raid or group members who were also eligible to loot the item. The system works like Item Buy Back but it won't be accessible if you've enchanted or slotted gems in the item.
New Forms
The Druid Cat and Bear forms have new art with five unique color schemes for each form and faction. Better still, the forms will be colored according to the hair and skin coloring of the Night Elves and Tauren.
Battleground XP
Players can now get experience for completing objectives and gaining honor in the Battlegrounds. You can opt in and out of the XP gain by paying a small fee to figures near the Battlemasters in Stormwind or Orgrimmar. Moreover, players who are defending a controlled capture point will gain a 50% bonus to honor from kills.
Dungeon Raids
In addition to various balance and reward changes, Dungeon Raids now allow players to extend instance IDs repeatedly on an individual basis via the social tab. This gives players more flexibility in completing each instance at their own pace.
Items
There are small calibrations to various values here. Most significantly, items that have a cooldown timer will require the player to wait out one full cooldown period after equipping the item before using the ability, so players who like to switch belts in the middle of a fight may find it more trouble than it's worth. On the plus side, mounts can be summoned much more quickly now.
Class and Profession Changes
Blizzard has instituted so many changes to the various classes, that it's impossible to summarize them. The Death Knight has been rebalanced so much that all talent points have been refunded, giving players a chance to respec their characters.
Interface
Loads of changes here as well, but the two that seem the most immediately useful as the double-paned quest log, the SHIFT-enabled item comparisons and vendor prices displayed even when you're not at a vendor.
Bugs
Squashed.
more here