The company revealed very little about it, not even a name. But a quote from Infiniti's Executive Design Director may shed a bit of light on the car. He talks about "more compact and less intrusive powertrains" giving freedom to design, and that this car has a "long cabin." This leads us to believe that this concept may feature some kind of alternative powertrain, perhaps hybrid or fully electric. It could even use a smaller version of Infiniti's variable compression engine.
We also think that this car may have a profile akin to the Jaguar I-Pace, with a much more cab-forward look. When Jaguar revealed the I-Pace, it made a big deal about how going to electric propulsion gave them the opportunity to rethink what looks luxurious, sporty and aggressive, since there wasn't an engine at the front to require a long nose. Infiniti's design director's words sound pretty similar.
We'll have more information and photos when the car is fully revealed at the 2018 Detroit Auto Show.