It also appears that Google worked with Blackberry to roll this out maybe a sign of things to come. http://betanews.com/2015/09/28/why-...ackberrys-handset-business-but-probably-wont/
There is another hardened Android out there which is a fork of CyanogenMod fork. Uses Pax but not grsec. Interesting info in their blog posts. https://copperhead.co/blog
Copperhead is not exactly praising Priv's security: https://twitter.com/CopperheadSec/status/662812090512510976 https://twitter.com/CopperheadSec/status/662852778788720641 https://twitter.com/CopperheadSec/status/669510825594494976
How else would they get noticed? Google worked with BB on the secure OS. IMO android is very likely to move in that direction with or without BB and a secure Android would threaten a company touting a secure version.