Blizzard has announced that Joyous Journeys has returned to Wrath of the Lich King Classic, which is a 50% experience buff, lasting even after Icecrown Citadel launches.
The roads in Northrend are icy and fraught with danger. To help you continue your journey, players will get the benefit of the Joyous Journeys experience buff*, which will increase experience gains by 50% for all players through level 80!