Blizzard has announced at Gamescom that Diablo III will have its first expansion, titled "Reaper of Souls." Little information is currently known about the expansion, outside of the fact that it's going to focus on the Angel of Death, Maltheal. It will include new enemy types and new areas. In addition, a new class will be added.
The new class is the Crusader and he will be a mid-range melee class using flails and shields, with mid-range magic. Something that a lot of melee characters struggle with on high difficulties is the fact that until they have sufficient gear, the enemies can almost one shot them while ranged can walk around dealing damage infinitely with no regard for the melee damage. This is being addressed with a new melee class in addition to new ranged enemies who will give Demon Hunters and casters more fun for their money.
Other additions appear to be focused on the endgame. More details will surely come out once Blizzard gets the official site up and running.
New updates are in, including it is confirmed that the level cap will be raised and there will be a return to the Pandemonium Fortress.
More Details: Blizzard Press Release.
Original Source: Polygon.