See dang’s comment way down. The link was originally to a very self-congratulatory press release from the marketing person, and later changed to a blog post with details and exposition from the CTO.
Purism’s style in press releases is pretty annoying, but I really appreciate the blog posts.
I backed the phone. I’ve backed most GNU+Linux replacements for my iDevices.
If it half-works it will have wildly exceeded my expectations!
I wish them the very best.