Thom is never the first with his guides. That's because he actually uses the cameras in the field, tests them thoroughly, and only then writes his book. Guides are available for the following cameras still being sold new:
Guides for older cameras:
A D6 Guide will be released in 2021. No Complete Guide for the Df or D4 series cameras was created or contemplated. Thom will continue to do books for other D7xxx and higher cameras for the foreseeable future.