"Subaru developing the basic platform, chassis and engine of the car, while Toyota concentrates on the design and engineering of the car’s cabin."
Taking the strongest assets of each company and combining them in to one car should make for an interesting vehicle.
To be honest, I can't see this being badged Supra by Toyota (as reported), as surely it doesn't fit the ethos of previous generations of that car. I would suggest this to be more like a Celica replacement if anything.
It's all about the twisties....