You haven't fully explored the world of Norrath until you've ventured into the Lost Dungeons! Very little information is known at this time, but Lost Dungeons of Norrath is destined to play an integral part in the ever-expanding gaming phenomenon known as EverQuest. ETA currently November
The big rumor about this expansion is that it will focus solely on dungeons and that the dungeons will be instance dungeons where all or part of the dungeon will spawn individually for each party. (Similar to the Hedge maze in PON)