The vehicles they showed us actually look pretty high-poly, theres a small chance there for the fmvs (If they have decided to keep that style of cutscene).
But I'm pretty sure a game engine could handle them.
I'm pretty sure ubisoft will do anything to make the series better.
They have a pretty good record until they started releasing Nintendo Wii games
The PC version of Driver: Parallel Lines felt bug free.
and Driver: 76 was ok.
But Ubisoft really fund the team money.
I'm sure they have the money Reflections Interactive (Ubisoft Reflections) need.