Quest:A Cold Winter's Night was released around Christmas this year, as a permanent quest.
Quest:The Beast of Ironfang was released as the winter scenario of 2005, as a permanent quest
There was not any particularly winter-themed adventure added at Yuletide this year
Also, And to All a Good Night, temporary
A Blizzard in the Hills was initially added as a limited-time scenario, but it was later brought again as a permanent adventure.
The winter event of 2009 was The Obelisk of Winter, temporary.
The Yuletide event of 2010 was The Great Palobread Man Roundup, temporary
There was a short event we've called Yuletide 2011