There has been a certain amount of confusion about what exactly is going on with emblems in Ulduar. We've 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. I'll try to distill the information that I found useful into a few bullet points.
- The EoVs in Uld-10 are the same as the ones from Naxx-25, and let you buy the same rewards.
- Relics from Naxx-25 are being added to the EoV quartermasters; nothing else is being added to them at this time.
- Tier 8.5 gear tokens (chest and helm) will be buyable with EoCs (from Uld-25). Tier 8.0 gear tokens will not be buyable in any way.
- There will be a new EoC quartermaster with the two 8.5 tokens and additional ilvl 226 gear for purchase.
The justification for T8.0 not being buyable for tokens is that they didn't want current Naxx-25 raiders stockpiling huge numbers of EoVs to buy stuff on the 3.1 release. This does make some sense, although there are other routes they could have gone with it. Anyway, it's good to have clarification.