Be aware that this reads a bit like fan fiction. If you are expecting a story that focuses on what occurs when major players in the supernatural world meet, you will be disappointed. If you want to see a rehash of old storylines and relationships, then this is the book for you. This is the first half of one book that is being sold to you separately, it leads to a cliff hanger (of course) and you will have to buy the second half of this book later this year.
This is an incredibly lazy effort by Jim with multiple scenes that could have been cut and made room for for the actual Peace Talks. Instead we just get fan fiction like scenes that do little to move the plot forward and generally rehash other books. We all love Michael Carpenter, but seeing him rehash the same advice given in the last 10 books just fills pages and little else. Laura Wraith having to work with Dresden and having sexual tension and a misunderstanding sound familiar? Plenty of that here. Wardens not trusting Dresden? Got you covered. Murphy having to remind Dresden not to treat her a normal frail mortal? In spades.
Sadly the book only gets interesting in the last few chapters and we never get any insight into what a gathering of powerful supernatural nations/entities actually does at a Peace Talk as Dresden is basically running around on a side quest most of the book, so don't expect any actual politics or new information on any of the major players.
Listen I love the series but this obviously was a way to get readers to pay twice for the same book and at the same time allow Jim to write a bunch of fan favorite fluff with little need to edit the book into something stronger.