Locations Raven Rock, Miraak Temple, Castle Karstaag and Telvanni Tower were also mentioned.
Bottom is quest header for Dragonborn quests. Compass markers denoting, clockwise, Telvanni Tower, To Solstheim, Raven Rock, Castle Karstaag, Standing Stones, To Skyrim, Miraak Temple. There may be dragon mounts (or it could be a scripted ride), new armour types - Bonemold, Chitin, Nordic and Stalhrim - and mounted spell casting may be on the way. Original story: It's unconfirmed, but it looks like the next Skyrim DLC will be called Dragonborn and take place on the independent island of Solstheim (East of Skyrim, North of Morrowind).
Update: Spears! Source code reveller Mardoxx has uncovered evidence of spears in the Dragonborn DLC.