Both retailer GameStop and Amazon have rather silently pushed back the release date for Mortal Kombat X on PS3 and Xbox 360 to a placeholder date of December 31, 2015.
The last-gen SKUs for the game by High Voltage Software, who were responsible for the PC version, were meant to be released alongside the next-gen version in April but were delayed until a vague "summer" release.
This marks the second time the last-gen versions of the game have been delayed. With them being pushed so far into the backend of the year, it's an indication that the main reason for the delay is to sell more copies during the holiday rush.
The install bases for PlayStation 3 and Xbox 360 are too substantial to ignore, so this is a messy, albeit understandable, situation. Of course, by now the question is whether Warner Bros. should even both at this point; by the holidays, I would suspect that there will be some kind of Komplete Edition for Mortal Kombat X on next-gen consoles that includes all the DLC. If they decided to cancel the last-gen versions, I wouldn't cry foul.