As both an engineer and a helicopter pilot I think this is brilliant. It will be simpler, safer, lighter, more reliable, less noisy, and less expensive.
I am curious about the fan acceleration/deceleration curves. That seems a bit challenging, but clearly Bell would want this anti-torque mechanism to be at least as, if not more, responsive than existing methods.
Claims of zero tail rotor speed on the ground are interesting, but one wonders how this will be sorted out for operation on low friction surfaces like water, snow and ice (currently of significant concern to me every flying day this winter
).
I am curious about the exact weight trade-off. The tail intuitively looks lighter and sleeker than a gearbox, control rod, swash plate, pitch links and normal tail rotor. Wiring will not be any heavier than a drive shaft and probably lighter. But the weight of redundant generators and motor controllers located at the main gearbox is of interest. We could take a gander at the size of the motors if we had a little data: how much horsepower (or KW if your prefer) does the tail rotor require on this helicopter?