This is a new universe unconnected with Spencer's previous work. There's certainly enough unanswered that a direct sequel is possible, and more stories could be told in this world, but it is a complete story. Contains sexual situations highly inappropriate for the minor children of even slightly prudish parents.
This book starts out very well, presenting a rather original world with enough detail to intrigue but not so much that it falls apart, and gives us several important characters that grabbed my attention and made me really care about what happened to them. And then we introduced some metaphysical stuff that's harder to swallow. It doesn't wholly fail, but it doesn't wholly work either. There's a strong theme about the humanity of genetically modified humans which is some mix of insightful and "please stop beating me over the head with the message". This is Spencer's strongest novel to date; it sucked me into the world very strongly, making me happy every time I picked the book up and frustrated to put it down. But I'm still scratching my head over whether I can deal with where the main plot ends up. Separately, I know that some people will majorly squick at some of the bad things the bad people do. For me, it's somewhere on the border of going too far; we need to know how bad the bad guys are in some detail to understand the character and motivations of our good guys, who have flaws of their own. But for some, it's going far enough over the line to inspire flamewars if not bookburnings.
I'm going to give this a 9 out of 10 because I want to remember the great things.
I don't want to post this without a plot summary, but I really have to go to bed.