Looks like the the rumours are true, the next World of Warcraft expansion will indeed by Wrath of the Lich King. The expansion was confirmed in the BlizzCon Souvenir Show Guide packed into those fancy goodie bags.
The picture, taken by Highamage, shows the brief article about the new expansion which will be detailed during the show.
Some of the highlights of the article include:
*Introduction of the Death Knight as a playable dark necromatic character class.
*New zones, quests, items and monsters packed into the Northrend, an icy continent that is home to the Lich King.
*Raised level cap to 80
*New battlegrounds featuring siege engines and destructible buidlings.
*More character customisation, including hair, dances and skin colour.
Wrath of the Lich King [Blizzard Forums]