Details of one of Cataclysm's L85 5-man dungeons, Grim Batol, has been published:
During a bloody civil war among the three dwarven factions of Ironforge, the Bronzebeards ousted the Wildhammer and the Dark Iron clans from the ancient corridors of the mountain city. In the wake of the defeat, the Wildhammers ventured north and forged a new home, Grim Batol, in the mountains of what is now the Twilight Highlands. However, although they worked tirelessly to create a better future for themselves, the Dark Irons, who established the city of Thaurissan in the Redridge Mountains, could not move beyond the memory of their defeat. Consumed by the desire for revenge and desperate to control the entire dwarven region of Khaz Modan, the Dark Irons led a two-pronged assault on the Bronzebeards in Ironforge and the Wildhammers in Grim Batol. Despite their past differences, these two embattled rivals joined forces and drove the Dark Irons out of Khaz Modan, decimating the armies of the treacherous clan's sorcerer-thane, Thaurissan. Yet victory carried grave consequences. Although Thaurissan's wife and queen, Modgud, was slain during the attack on Grim Batol, her death tainted the mountain fortress. While the Bronzebeards rebuilt their glorious city of Ironforge, the Wildhammers felt forever changed by the horrors they witnessed at Grim Batol. They fled their cursed home and never returned.
Check out Blizzard's official Grim Batol
page for more details.