Edit: Seems like Calxeda won't design its own ARMv8 core but will use a ready-made core from ARM Ltd. instead:
"Announced licensees of the new processor series include AMD, Broadcom, Calxeda, HiSilicon, Samsung and STMicroelectronics." http://www.arm.com/about/newsroom/arm-launches-cortex-a50-series-the-worlds-most-energy-efficient-64-bit-processors.php