Another World of Warcraft: Wrath of the Lich King Interview

Whether Blizzard can actually achieve its plan of releasing a new World of Warcraft expansion every year remains to be seen. Wrath of the Lich King opens up the new continent of Northrend and brings with it an increase in level cap (to 80), the introduction of Hero classes with the Death Knight, siege weaponry and destructible buildings in Battlegrounds and further additions to keep fans hooked forever.

http://wowbreak.com/stories/page/2