User blog comment:Pokweeismypsn/Bethesda: We don't "carve out" DLC content from games before release/@comment-68.179.18.88-20110714033741/@comment-71.113.233.67-20110716181433

Knights of the Nine was more of a drawn out quest than an expansion imo, with the other three we saw new lands to explore, a main quest, and multiple side quests.