I belive that they will burn out some double MHs comared to the 1080 series
Nah... I believe it'll take a lot of time FOR US to take full advantage of these cards.
My guess is that after about a month they'll figure a way to use the tensor cores to improve the hashrate but if the gain is big enough it'll only be made available privately. The rest of us will get a miner with a dev fee like 6 months later, after enough people have managed to crack down on these cards.
An alternative scenario is that there will be no mining farms with the 20 series cards and therefore whatever miner for the 20 series is developed, it'll be available for the public. However I'm more thrilled for Ray Tracing enabled games than mining!