BioWare is set to hold a panel at Comic Con this Saturday in the US (so early Sunday morning for us), where it's expected the developer will reveal two new DLC packs on their way for Mass Effect 3 - one a single-player add-on called Leviathan, and the other a multiplayer add-on called "Earth".
Despite the impending official announcement from BioWare this weekend, voice-actor, Anthony Skordi, for the Leviathan DLC has already confirmed its existence, while Microsoft's Major Nelson outed the multiplayer DLC in a recent blog post
. The Leviathan DLC is purported to follow a confrontation with a Reaper called Leviathan who turns on his own kind. More info can be found over at Eurogamer
, but it contains spoilers, so beware.