https://www.forbes.com/sites/gordonkelly/2017/08/06/apple-iphone-8-touch-id-face-id-design-price-cam
Previously my sources had indicated Apple may integrate Touch ID into an enlarged power button as a backup, but it appears Apple is now prepared to take a much bigger gamble.
As leaked in its own software, Apple will instead move all iPhone 8 security to ‘Face ID’ - a new facial recognition that will hopefully work better than Samsung’s erratic implementation in the Galaxy S8 and Galaxy S8 Plus which struggles in bright sunlight, low light and when wearing glasses/sunglasses.