The Teenage Mutant Ninja Turtles: Mutants in Manhattan has all but been confirmed.
The game was first leaked at the start of December, with the game being listed on the Australian Classification Board. Back then, we figured out that the game would be developed by Platinum Games, and published by Activision.
Platinum Games is best known for developing Bayonetta, and alongside the speculated Teenage Mutant Ninja Turtles game, is making Xbox One exclusive Scalebound.
For even more evidence, Xbox Achievements has a complete list of achievements for the game. With the startling amount of proof, and still no confirmation, pureXBOX has released 5 screenshots for the game(which can all be found here).
The game has a similar style to the 2015 Transformers: Devstation, also developed by Platinum Games.