Looks like the rumors were true. The good news, Mortal Kombat X will indeed be getting another round of DLC content. The bad news, well, we have to wait till 2016.
No specifics of who or what will come with the DLC just yet but WB has confirmed that it will contain new playable characters, skins and a new environment. WB also states that all of said content will be available in the first half of 2016.
For me, I really hope those new skins are for the new characters. One of the things that annoys me the most about the Mortal Kombat franchise is how they will introduce all of these new characters and then completely ignore them.
Scorpion, Sub-Zero, Sonya, Jax, Johnny Cage, Kitana, Kung-Lao and all of the other classic characters all have gotten tons of new costumes either as DLC or unlockable in game. Meanwhile, all of the brand new characters like Cassie Cage, D'Vorah, Takeda, Kotal Khan and such haven't gotten any new costumes at all. All they have are their defaults and the unlockable alternates.
As for the new characters, all I want is Fujin and Sareena. Those are the two characters I have wanted to see return to Mortal Kombat for years. I know they were in Armageddon but I don't count them because that game barely had a story to begin with and they were only included just to fit every MK character ever made into the game.