Greatfather Winter is visiting the great cities of Ironforge and Orgrimmar - courtesy of the fine folks of Smokywood Pastures and he's spreading cheer in celebration for the Feast of Winter Veil. But, all the cheer-spreading is making Greatfather Winter hungry, and he's looking for adventurers to get him his daily fix of milk and cookies.

Revelers
During the Feast of Winter Veil, the innkeepers bring out holiday decorations to provide a festive atmosphere for their patrons. Who knows what might happen if you /kiss a reveler standing near a sprig of mistletoe....

Smokeywood Pastures' Missing Shipment
Smokeywood Pastures needs a few brave adventurers to investigate the disappearance of a shipment of holiday goods. Rumors are the shipment is in the possession of the Abominable Greench, found somewhere in the snowy regions of the Alterac Mountains.

Metzen the Reindeer 
Disaster has struck! Metzen the Reindeer has been kidnapped! Metzen is one of Greatfather Winter's eight reindeer - and property of Smokywood Pastures. The Jinglepocket Goblins have received two ransom letters from groups claiming to have Metzen. Concerned adventurers should visit Ironforge or Orgrimmar for more information.

Jinglepocket Goblins' Fare Shops
The Jinglepocket Goblins have set up their seasonal fare shops in major cities. Adventurers can purchase many holiday favorites - including Greatfather's Winter ale, candy canes, gingerbread cookie recipes, and mistletoes.

Snowballs
Whether you pick them up from your local vendor or ask a friendly engineer to craft them for you, no feast of Winter Veil is complete without some frozen projectile-weapons. Get your mitts on some snowballs and say, "Merry Feast of Winter Veil" the old-fashioned way!

Snowmen
Accompanying Greatfather Winter in his journeys across Azeroth are his loyal troops of snowmen. They can be found wandering around Ironforge and Orgrimmar, bringing with them the chill breath of winter into even the warmest climes.

Winter Veil Bosses
The denizens of the dungeons of Outland are also getting into the holiday spirit, and some dungeon bosses even wear festive Winter Hats just like Greatfather Winter's. Defeat a Winter Veil boss, and the boss' hat is yours!

Winter Veil bosses of Outland:
Captain Skarloc (Escape from Durnholde Keep) - Red Winter Hat
Nethermancer Sepethrea (The Mechanar) - Red Winter Hat
High Botanist Freywinn (The Botanica) - Red Winter Hat
Grand Warlock Nethekurse (Shattered Halls) - Green Winter Hat
Grandmaster Vorpil (Shadow Labyrinth) - Green Winter Hat
Exarch Maladaar (Auchenai Crypts) - Green Winter Hat

From December 25th to January 2nd only

Gift-Giving 
In the quiet, early hours of the 25th of December, the industrious goblins of Smokywood Pastures are already awake. As a much-deserved reward for the noble adventurers throughout Azeroth, these generous harbingers of the holidays deposit gifts underneath the decorated trees in Orgrimmar and Ironforge. Keep a keen eye out for these presents, as they're there for the taking!

source: http://www.worldofwarcraft.com