Soft Sailor has this initial release notes:
1. Argent Tournament:
- New 5, 10, and 25 man instance to WoW.
- Argent Coliseum – an event similar to the Ring of Blood in Nagrand.
- Raid level root is higher than Ulduar.
- Black Knight is back.
- Two new quest hubs in Icecrown – Cult of the Damned, and a Vrykul outpost.
- Isle of Conquest – a new battleground.
- New dailies and new rewards.
- New heirlooms.
2. Class changes:
- Death Knights: dual wielding makeover.
- Druids: new Druid forms – Cat Form: Tauren & Night Elf; Bear Form: Tauren & Night Elf; Old bear and cat forms to be removed.
- Hunters: ammo costs, pet scaling, and crowd control.
- Shamans: Resto Shamans changes, and new Shaman totem interface.
3. Item changes:
- Chest heirlooms with 10% XP bonus.
4. Profession changes:
- Epic gems.
- Updates to: Alchemy, Enchanting, Engineering, Herbalism, Inscription, Jewelcrafting, Leatherworking, Mining, Skinning, and Tailoring.
5. Mounts and Travel:
- Ulduar Plagued and Black Proto-Drakes removed.
- New zeppelin route between Thunder Bluff and Orgrimmar.
- Portals in Stormwind and Orgrimmar leading to the Stair of Destiny at the Dark Portal.
- Class travel skills reduced to Level 16.
- Epic land mounts trainable at level 40 [was 60].
- Regular flying mounts speed increased to 150% gain [was 60%].
- Regular flying mounts trainable at level 60 [was 70].
- Regular land mounts trainable at level 20 [was 30].