Just because they haven't been announced doesn't mean they won't be included.
Considering the ubiquity of Daedra (they can be summoned anywhere in Tamriel where there is somone to summon them), I think it would be deeply dissapointing if the majority of the types we already know, at the least, were not in the game. The Dark Elves who live near the Skyrim border are known to have had dealings with Dremora, Golden Saints (Aureal), Mazkan (Dark Seducers), Scamps, Atronachs, Xivalai, Ogrim and Winged Twilights. All of these save the Ogrim and Winged Twilights appeared in Morrowind AND Oblivion (Mazkan may have been missing from Morrowind). It is true that the Golden Saints and Mazken only came into Oblivion through the SI expansion, though they should have been in from the beginning. Whatever the case, I would hope the devs, knowing how well loved their uniquely categorized take on daimons and those who trafficke with them are, will have all our favourite Daedra peoples returning in all their glory.