You can now claim your free Hearthstone Kobolds & Catacombs packs

Shortly after the Hearthstone expansion Kobolds & Catacombs went live, Blizzard discovered that the game wasn't behaving exactly as it should. Some players were experiencing delays in receiving new daily quests, because of the load placed on Blizzard's infrastructure by the apparently-unforeseen popularity of Dungeon Runs. 

Free packs are here, and can be found in the gift area of Battle.net (the icon is in the upper-right corner, next to your name)

EDIT - Playing the Dungeon Run mode , which is a free addition to Hearthstone, will reward players with Kobolds & Catacombs card pack. Repeat this till you earn 3 card packs, so basically you are getting 6 free card packs. Enjoy!