If I recall correctly from one of the few interviews I read a while ago, this book is one that Bujold has thought about for many years, but was waiting for society and her readers to catch up to her. It goes back to Cordelia, but moves forward from her vicereine job (Emperor-appointed ruler of the planet) on Sergyar. A great deal of the history that she shared with Aral, and knew about even when she didn't share it, has come forward in time to be woven into the fabric of her life choices now. In this story, three years after Aral's death, Cordelia is now revisiting hopes and dreams and desires that she put aside for fourty years of work at Aral's side.
With the "Red Queen" title and the DNA cover, I was expecting a lot more evolutionary biology in this story. What I got instead was another little slice of Cordelia's... bestowing of redemption, most particularly on herself and Aral's former aide. There were more hearts broken by Aral's death, but also more freedoms created, than we had been privy to knowing during the end of Cryoburn. And I appreciate how Miles and his family contributed to the satisfying conclusion all 'round this time, even though the main focus was Cordelia.
This book also unexpectedly answered a question that I've had since Diplomatic Immunity regarding the Cetagandans. So that was a nice bonus. Not that I like the answer, but at least it was reasonable enough in context.
For the love of all that is good and right in fiction reading, DO NOT pick this book up unless you have at least read Cordelia's Honor, and preferably also Warrior's Apprentice and Brothers in Arms. Really, you should have a full grasp of Cordelia and a reasonably good one of Miles before reading this. Mom has read Cordelia's honor, Cetaganda, and Komarr, so I think she has enough background to move with this one. However, I think she needs another year away from Dad's death before embracing this change.