Meant to replace the current 652 and 653 chips, the Snapdragon 660 is touted as the new king of mid-range chips, and has been recently benchmarked in AnTuTu with impressive results.
The Snapdragon 660 is an octa-core processor which uses custom Kryo CPU cores. Four at 2.2GHz, with the remaining 4 at 1.9GHz.
Recently though, the device that was housing the chip was revealed: A 2K screen, a whopping 6GB of RAM, 64GB of internal storage, and a Dual Rear Camera setup. The device was also running on Android 7.1.1 Nougat with a February 5, 2017 security patch.
If a mid-range phone were to have these specs combined with a reasonable price tag, then that would certainly be a treat.
There are actually rumors of the SD660 being used for the Xiaomi Redmi Pro 2, which is expected to launch sometime this month. Regardless, we can expect to see this chip on new devices this year.