Seasonal quests for Winter Veil Festival (Christmas). New NPCs appear around the bank in Ironforge, in the town square in Stormwind, in every inn, and various other places.
First, talk to the goblins and get their quests; buy five holiday spices and both recipes (Gingerbread Cookies and Egg Nog). Then talk to Greatfather Winter (in Ironforge/Orgrimmar), next to them.
Then buy 5 Ice Cold Milk, any drink vendor or innkeeper should sell them.
For Alliance, there is also a quest to learn the history – not sure who has this on Horde side. The NPC is the other side of the bank steps in Ironforge, and you then have to run to the Explorer’s League and back to King Magni. This gives good Ironforge reputation.
Next, gather five small eggs. Birds in Westfall, Teldrassil, Mulgore, and harpies in Durotar or the Barrens should drop them often.
Make the cookies – you need cooking skill, but only level 1 to do this. For those below 30, this is all you need do, and can return to Greatfather Winter for hand ins. You will be given a package containing either 10 copper bars, 4 bolts of linen, or similar rewards. They don’t match your own professions, of course. You will also get a care package (of food and drink) in the mail.
If you are 30+, there’s another quest, but it requires a slow spawn, so it’s better to leave this for a few days; 6am works out ok. Go to Southshore, and run to Alterac. South of the Growless Cave, between three trees in the snow area, is a snow man. Talk to him. Then check the yeti area in front of the cave, and to the west of the ruins of Alterac – I have seen the Abominable Greench spawn in front of the cave, in the first clearing, as well as in front of the Alterac walls to the east. Level 37 elite. Lots of snowballs spawn in the snow areas, so have fun.
Reward for this is a recipe. Gloves of the Greatfather, Elixir of Frost Power, Snowmaster 9000, Edge of Winter are the ones I have noticed so far. There should be a tailoring and enchanting reward as well. You will also have mailed to you a snowman disguise, which requires a snowball to power it.
If you are 40+, you will also get the Metzen quest. Go to either Searing Gorge or Tanaris. In Tanaris, it’s the pirate compound in Lost Rigger Cove, the building behind Andre Firebeard. Clear mobs around the reindeer, then sprinkle your dust. The kidnappers are three or four level 45s.
Return to Greatfather Winter for rewards.
My level 60 character was the only one that got an extra reward for a separate quest from Greatfather Winter: 5 preserved holly, in return for 5 gold and one deeprock salt.
Finally, kissing a reveller – either mistletoe (spirit buff for another person), or holly (make your mount into a reindeer).