According to Reddit poster derptemp6698, there will be upcoming DLC for Mass Effect 3 multiplayer that will focus on Earth and the extended ending that Bioware has been working on.
Mass Effect 3: Earth:
The fighting is fiercest when it’s your home at stake! Mass Effect 3: Earth adds mods, gear, and new maps for Rio, Vancouver, and London. It features 3 new weapons: Piranha assault shotgun, Acolyte pistol, and Typhoon light machine gun. Six new human N7 classes are also available: Destroyer, Paladin, Demolisher, Slayer, Shadow, and Fury!
And as a bonus, Mass Effect 3: Extended Cut:
An expanded ending for Mass Effect 3. Additional scenes and an extended epilogue reveal the impact of Shepard’s choices on the future of the galaxy.
These have yet to be confirmed by EA and Bioware but they seem to be inline with Bioware’s plans for the game, especially the Mass Effect 3: Extended Cut DLC. Mass Effect fans will want to keep an eye out for any more information that may confirm these DLC packs for the game.