Dibella's Watch adds an entire new continent to Oblivion. It comes complete with a major city, castles, towns, villages, farms, monasteries and all the good stuff that makes up a Medieval landscape. There's also fighting to be had and quests to be made!
The area in the west previously added and uncolonized is being worked on now. I've started by making the area around Sundown Peak a bit more interesting. Now it is a picturesque valley.