This won't be a 918/P1/LF rival, they're extreme hypercars. This will be another shot across the bow of the 911 Turbo, as well as the new baby McLaren and oft-wished-for baby Ferrari.
I guessed at 2000 kgs, but batteries are ridiculously heavy and that's roughly the weight of them in the aforementioned hypercars with roughly the same power output from their hybrid systems. Assuming the new GT-R will still have a big engine and 4WD, I can't see them removing 200kg of weight from elsewhere in the car to compensate. Mizuno-san has already said that he wanted the GT-R to be heavy as it settles down better on the road, so clearly he's happy with a bloater of a car and just chucking more power and technology at it.
Whilst I'm glad that stuff like that exists, for me that's not the way forward.