Skyrim may just be getting bigger as enterprising Skyrim PC players have found out with a host of new filenames ("DLC 2", "Dragonborn") in the new PC update. What the files hint to are 4 new armour types, Quest markers for Solstheim, Telvanni, Castle Karstaag, Raven Rock and Miraak Temple as well as the possibility of Dragon mounts with dragon riding animations.
Bethseda parent Zenimax trademarked "Dragonborn" earlier this year so the chances of these files being related to DLC is high.