http://www.wowwiki.com/World_of_Warcraft:_CataclysmMajor expansion changes and updatesEdit href= Edit
* Player level cap increased to 85.
* Six new high-level zones: Mount Hyjal and Uldum in Kalimdor; Vashj'ir and the Twilight Highlands in the Eastern Kingdoms; Deepholm in the elemental plane of earth; and the PvP zone and daily quest hub Tol Barad.
* Two new player races, the worgen of Gilneas for the Alliance and the goblins of the Bilgewater Cartel for the Horde. New leveling zones added for these two races include Gilneas, the Isle of Kezan, and the Lost Isles.
* A dramatic alteration of Kalimdor and the Eastern Kingdoms due to the Cataclysm, resulting in massive environmental changes, as well as questing and progression changes, for nearly every zone, resulting in new leveling experiences. This includes new starter areas for the gnomes and Darkspear trolls, faction changes for some zones (such as Hillsbrad Foothills) and, with the environmental redesign, the ability for players to fly on both continents. (The blood elf and draenei content will still be instanced and limited to ground mounts only.)
* Seven new high-level dungeons and three new raid instances, all available in regular and heroic modes (with raids in both 10- and 25-player varieties), as well as two heroic revamps of classic dungeons (Deadmines and Shadowfang Keep). This will also include Blizzard's new Flexible Raid Lock system, a change to raid functionality which includes the ability to move between 10- and 25-player raid groups, combine or split groups, and vary regular & heroic attempts.
* New PvP opportunities including the Tol Barad zone and a PvP-instanced dungeon, Baradin Hold, as well as two new battlegrounds Battle for Gilneas and Twin Peaks.
* Class redesign (coming immediately prior to expansion launch in Patch 4.0.1 but optimized for the expansion) including new talents and spells, simplification of talent trees, and reorganization of class buffs.
* Revamp of character and gear stats, including elimination of some stats and major changes to base stat operability (such as intellect creating spell power, strength and agility affecting attack power, etc.) This includes the addition of Reforging to the game, giving players the ability to add certain stats on gear in return for removal of others.
* New race/class combinations (see the chart below) which will be available to all players in Patch 4.0.3.
* New Archaeology profession.
* Level cap raised on all main and secondary professions to 525, with many new items, patterns and rewards.
* A new Guild advancement system, which includes guild leveling, achievements and rewards.
* Consolidation of previous expansion set currency systems; rewards will include two PvE currencies, Justice and Valor points, as well as two PvP currencies, Honor and Conquest points.
* New technology enhancements including support for DirectX 11 features and hardware cursor in OpenGL mode, additional video options and a new water rendering engine
