Vrykul

From wow.incgamers.com

A race based on Northrend, thought to have disappeared thousands of years ago. They recently re-appeared at the start of the Northrend invasion by the Horde and Alliance forces to slay Arthas the Lich King.

The Vrykul are 13 foot tall, Viking-based humanoids. They centre around the fortress of Utgarde Keep, which is close by to Valguarde, the human settlement in the Howling Fjord.

This image below is concept art displayed at BlizzCon after the announcement of the expansion:Wrath of the Lich King.