The game is finally announced after rumors of it happening appeared online a few weeks ago. The game follows the strongly received original Injustice: Gods Among Us that came out in 2014 on many platforms. We will likely learn more during E3 so stay tuned for more information.
Source: NeoGaf VIA Business Wire

Press Release

Warner Bros. Interactive Entertainment and DC Entertainment today announced Injustice 2, the super-powered sequel to the hit game Injustice: Gods Among Us. The newest game in development from the award-winning NetherRealm Studios features a massive roster of DC Super Heroes and Super-Villains and allows players to build and power up the ultimate version of their favorite DC characters. Injustice 2 will be available for the PlayStation®4 computer entertainment system and Xbox One in 2017.
Injustice 2 offers the latest DC fighting game experience that expands on the previous title’s larger-than-life showdowns. Every battle defines you in a game where players personalize iconic DC characters with unique and powerful gear earned throughout the game. For the first time gamers can take control of how their characters look, fight and develop across a variety of game modes.
The game boasts the biggest DC roster ever in a fighting game, including Batman, Superman, Supergirl, Aquaman, Atrocitus and Gorilla Grodd. Battles will be states in large iconic arenas including Metropolis, Gotham City and Atlantis.
But we didn’t want to stop there. At NetherRealm, we always want to make games that are fun, challenging and innovative. We strive to give players a level of control that makes playing our games a truly personal experience. For that reason, we have introduced a brand new Gear System, allowing players to build their own version of Superman, their Batman and ultimately, their Injustice Universe.
The Gear System uses RPG-like mechanics to reward you with loot drops every time you play the game. With each loot drop, you will earn character-specific gear to outfit and power up your roster – changing not only the look of each character, but your fight strategy and your personal approach to every match. As you gear up your characters, you’re building a roster of DC Super Heroes and Super-Villains that reflects your choices, and your preferences, which can be vastly different than your opponents. A few play sessions in, you can expect your Aquaman to look and play different than anyone else’s Aquaman you may come across.