Yes 1500$ is very expensive. He should cost 1000$. In that case small number of people will buy and 10 cores and 8 core processor. But Intel will decide... Anyway and for 1000$ small number will buy him, but I afraid they will finish with him same as NVIDIA with TITAN Z. 8 cores will not be interesting for 1000$ because there are better models and better model will be too expensive.
Because that's last generation before new socket, new chipset and different memory profile maybe Intel should sell 8 cores for 700$ aand 10 cores as 1000$. 6 cores to stay 400 and 550$.