I thought we knew they were in the game a while ago?
Anyway, it's nice to know regardless, Dwemer ruins were a fairly interesting sort of dungeon, and considering that one of my bigger complaints with Oblivion was the blandness of its game world, I will welcome being able to explore more interesting environments in Skyrim.
They are both correct.
High Elf = Altmer
Dark Elf = Dunmer
Wood Elf = Bosmer
Orc = Orsimer
Dwarf = Dwemer
Unfortunately, it seems some people have a hard time grasping this, you'd think a fandom that puts so much emphasis on a setting's lore would pay more heed to said lore, yet there are apparently those who seem to even fail to realize that "dwarf" and "Dwemer" mean the same thing in the Elder Scrolls and both names are in fact used in the setting.
Hopefully we get some new lore into the Dwemer and some interesting side quests that lead us to more info on how/why they disappeared.
I wouldn't expect to see much in the way of new lore on them, after Morrowind, I don't really see too many things on them we don't know that Bethesda could reveal without ruining any sense of mystery surrounding them.