here has been a certain amount of confusion about what exactly is going on with emblems in Ulduar. WoW Inser has known for a while that Emblems of Valor, which currently drop from 25-man Naxxramas, are going to drop in 10-man Ulduar, and that Ulduar-25 is going to drop a new badge: Emblem of Conquest. However, there were some rumors that the EoVs from Uld-10 would be a different "color" than the EoVs from Naxx-25, enabling purchase of some gear for the new EoVs that would not be buyable with the Naxx-25 EoVs. There have also been various theories about whether Tier 8 tokens would be buyable with emblems, like some of the T7 tokens are now.
Vaneras has gone and clarified these questions and more, in a FAQ post on the European forums.