Bioware have officially announced that the Mass Effect 3 Leviathan single-player DLC will be released on August 28th, 2012 for PS3, Xbox 360, and PC. Please note that on Playstation 3 in Europe, it will be available on August 29th. The official blurb is:
Something lurks in the dark corners of space, something powerful enough to kill a Reaper. Shepard must discover the most closely guarded secret in the galaxy before the Reapers silence it forever. Discover more about the origins of the Reapers as you race across the galaxy to find the Leviathan. Unravel the dark history of the Reaper Race before it is too late. Coming later this summer there is no war, only the harvest.
Taking place during the events of Mass Effect 3, players will be thrust into the darkest corners of space where they will hunt a mysterious being rumored to be powerful enough to destroy a Reaper. As they race against time, they will begin to unravel the secret of the Leviathan. Explore uncharted systems and new areas on the Citadel, interact with brand new characters, unlock the AT-12 Raider shotgun and M-55 Argus Assault Rifle and discover more about the mysterious history of the Reapers. Available on PC, Xbox 360 and Playstation 3. Cost is $10 or 800 Microsoft points.