Many of us expected to hear the expansion to be entitled "Cataclysm"， announced at this year's BlizzCon, but it's no surprise to us that loose lips may have stolen Blizzard's thunder. Do keep in mind that nothing has been officially announced, and while the information seems credible, we still must classify this report as a rumor.

Below are the allegedly leaked details of Blizzard's upcoming expansion, "Cataclysm":

Level Cap: The level cap will be raised to Level 85.

"New" Classes: No new classes per se, but some classes previously unavailable to some races will now be playable, and they include:

Human Hunter

Orc Mage

Night Elf Mage

Dwarf Mage

Blood Elf Warrior

Dwarf Shaman

Undead Hunter

Tauren Paladin

Tauren Priest

Gnome Priest

Troll Druid

New Races: The previously speculated Goblins and Worgen are confirmed, with the Goblins being on the Horde, and the Worgen on the Alliance. Worgen will also have both a Human and Worgen form which they can shapeshift between. Both forms will be customizable.

Old Azeroth, Meet New Azeroth: Keeping with the theme of the expansions name, a cataclysmic event set in motion by the characters Deathwing and Azshara will dramatically shift the landscape of Azeroth, and this will result in a number of gameplay changes. For one, Azeroth will make use of some of the more recently introduced features like the phasing system from Wrath of the Lich King, and daily quests.

Other details on Azeroth changes from the MMO-Champion report:

The Barrens will be split into two separate zones of two different level bands.

Azshara will become a low level (~10-20) zone.

Some of the zones like the Thousand Needles will be flooded.

Durotar is wrecked and apparently Orgrimmar could be destroyed. A new Orc city is rebuilt over the course of the expansion.

Gnomeregan will be part of the expansion as well and gnomes might be able to reclaim their capital. (The last part is still unconfirmed)

Wailing Caverns will be become a lush tropical area as a result of the druid's magic.

The Blackrock Spire will erupt and a new version of Blackrock Mountains will be available, apparently Ragnaros will be back too.