Blizzard have confirmed that they do not intend for Emblems of Valor to be used to purchased Ulduar gear.
However, relic items from Naxx have been added to the Valor quartermasters:
Sigil of Awareness
Idol of Awakening
Libram of Resurgence
Totem of Hex
So if you haven't managed to pick up your Idol of Awakening yet - don't fret, you'll be able to purchase one with valor badges soon.