http://bloody-disgusting.com/news/3248453/the-first-diablo-iii-expansion-might-be-titled-the-dark-below/
Blizzard recently filed a trademark application for a game-related project called The Dark Below that will feature virtual currency and items. That’s all the solid information we have on it for now, but it sure sounds like the title for that Diablo III expansion they promised so long ago.
Just last month Blizzard teased a big Gamescom announcement that would “capture the attention of the Heavens, Burning Hells and all the shadowed places that lie between.” That’s definitely related to Diablo III. We won’t know for sure if this is too until Gamescom kicks off on August 21st.