Blizzard announced that they plan to create their own voice chat service to multiplayer back in October.
This week, Blizzard announced the launch of that service to all of their users.
Called Blizzard Voice, it will allow players to talk to their friends and friends of friends from a range of games, or just from their Blizzard Launcher, meaning it is compatible with all games and services. However, it will only work with friends or friends-of-friends, meaning you can no longer chat with any player in-game.
Blizzard Voice has arrived! Be sure to update your Blizzard Launcher before trying to give it a go ? pic.twitter.com/P3T2lEMVWM
— Blizzard Ent (@Blizzard_Ent) October 20, 2016
The voice service also has a number of customisation options, and you can mute and adjust the volume of members in your party on an individual basis.
To get access, you simply need to update the Blizzard Launcher to the latest version.