I do it on my college alum slack channel, but I recently wrote one up that made it to the front page of HN:

https://ahalbert.com/reviews/2023/06/04/the_culture_map.html

I took some inspiration from the book review contests of "Astral Codex Ten"

https://astralcodexten.substack.com/p/your-book-review-publi...

Not GP, but https://fourminutebooks.com comes to mind. It's also just incredibly useful to get a "4 minute precis" and decide whether or not it's worth it to you to spend more time on that book.

I do the same, since the Start of the year. I write personal notes and if a book really gets to me I will write a public review