Derek's book notes inspired me to post my own [1]. Making the effort to clean up my notes and go through them strengthens the lessons learned.
However, I'm not sure how valuable these types of notes are for others. Often I find a passage that resonates with me falls flat for others, and vice versa. It depends on other books you've read, life context, etc.
I do try to indicate who might find the book helpful, or who should probably skip it.
[1]: jamesstuber.org/booknotes