Updating all of your Blizzard games is about to get a bit easier. Starting today, players can download the open beta version of the new Battle.net desktop app. Over the next few months, StarCraft II, World of Warcraft, Hearthstone: Heroes of Warcraft, and Diablo III will all be automatically updated to the new app, allowing all games to be patched or downloaded right from the singular new patcher. Once the open beta ends, every game will update and utilize the new patcher.
Source: Battle.net Desktop App