User blog comment:Timeoin/5 Questions about TES Online that noone but me cares about/@comment-4705438-20121128222246

4. The question has already been answered in the Ebony Pact Q&A Part 2. Dunmer Houses will be present. There is some additional info on House Telvanni, who have refused to ally themselves with the Nords and Argonians.

There is a catch, however, the same Q&A states that the player will not be able to join the Houses, at least on the game's release.