Apparently, this depends on the laptop. Some laptops have a hardware mux that allows you to switch the display to the NVIDIA GPU, similarly to how the old Hybrid Graphics worked. On those laptops, there should be a BIOS setting.
On laptops that don't have that hardware mux (i.e. where the display is hard-wired to the Intel display engine), then you currently cannot use the NVIDIA GPU for display, though you should still be able to use it for CUDA and offscreen rendering.
We currently do not have plans to support display on Optimus systems where the display is connected to the Intel hardware, but as you said, it's something we'll probably end up having to look into in the future, to at least provide some basic display sharing. I can't promise anything, though.