It is dependent on season, so you wont see them until season starts which will be May 28th.
Please note: Valor will not be earnable between the launch of Cataclysm and the first weekly reset in each region. Conquest will become available starting with the second weekly reset on May 28, with the launch of the first Cataclysm PvP season.
Going by this, it means the vendors won’t be added in until next Tuesday. Most likely to let people level up in the meantime and catch up in honor i guess.