The story is meant to start with a punch as the opening scene has Dresden receive a call from Susan in which he learns that a) they have a daughter, and b) she's been taken. Unfortunately, the "secret child out of left field!" plot has been done so often that what should have been shocking was more eye-rolling. 
 I feel like if a major reveal like this is going to happen, there needs to have been some clues (even if they weren't seen as such at the time) leading up to it. The girl is something like eight years old, that's eight years of Susan keeping a perfect secret and never acting strange. At the very least, some of this could have been retconned, with Harry suddenly making sense of some odd comment or behaviour that took place between novels. The way it's done here, however, just feels like a cheat. 
 Thankfully, though the cheat is rather central to the plot, it's the only real criticism I can offer. This book ramps up the danger and brings about several showdowns that have been building up for the better part of the series. 
 One reviewer complained that we never really fear for Dresden's safety any more because he's just become so incredibly powerful. And that is true to a certain extent. I mean, he still struggles, and his tasks are difficult, but he spent the better part of the final showdown wearing what amounted to invincibility armour. 
 However, I think that there are two factors that balance this out. The first is that we are continuously introduced to even more powerful enemies as Dresden works his way up the supernatural food chain (not to give away too many spoilers, but everyone's favourite one-eyed deity makes an appearance in this book). The second is that the danger to Dresden has shifted (and did so in a very clear way back in Death Masks). It's not the safety of Dresden's physical body that is keeping me at the edge of my seat, but rather the safety of his self as he makes impossible choices in order to get all that extra power. 
 Besides which, I'm not sure this series could have held my attention if he was still just fighting local werewolves and the odd rogue wizard. The early books were very formulaic, and seeing Dresden meet and beat the same kinds of dangers over and over again would have quickly lost its luster. A good series knows to ramp up the stakes, shake things up, and force the main characters to either change or break. And I think that Changes does this beautifully. 
 Speaking of changes, I mentioned to a friend after I finished Turn Coat how funny it was that the series had entirely dropped the whole "Wizard P.I. with an office" bit it had ridden so hard in the early books. In fact, I couldn't remember Dresden's office having been brought up at all in several books, and wondered why he was bothering to keep up the rent now that he's a Warden and that all his clients have his private number, so to speak. So, of course, Butcher heard me and responded, and I got a little chuckle out of that (largely due to his perfect timing). 
 (view spoiler)[I had a few problems with the book that require spoilers. The easiest to deal with is the ending, which was a really good cliff-hanger that I hope pays off properly in the next book, but just kept dragging on as Butcher couldn't seem to just stop writing. It was a shame, and I felt it reduced the impact of what would otherwise have been a very satisfying close (satisfying if the payoff in the next book works, of course). 
 There was a colonialist undertone to the book that didn't quite sit well with me. I mean, Dresden literally dresses up like a Conquistador to go kill Mayan gods, and there's a bit in there about how this will free the Mayans from the evil of their gods, and that all hit a little too close to the rhetoric that justified the wholesale genocide of aboriginal peoples. Sure, everything had a neat explanation in the context of the book, but oof! It came off really tone-deaf. 
 Which leads me to my last bit. The series started off with an undersmell of sexism that has, off-and-on, gotten better. Here, however, women and little girls are tortured and killed for the purposes of giving Dresden his manly manpain. Again, it's a narrative cliche that has been done to death, and that has reinforced structures that cause real-world harm. While I certainly found the story very compelling, and it's satisfying to watch Dresden evolve through the choices he makes, it would have been nice to try something a little different for once. (hide spoiler)] 
 I also wanted to make a little note on James Marsters's reading. For a while after I had a baby, I had to do the bulk of my reading through audiobooks because free hands are so hard to come by with little ones around. And while I've mostly transitioned books like the Dresden Files back over to paper copies now, I've stuck with audiobooks for this series through the sheer pleasure in listening to Marsters's performance. While it's still absolutely wonderful, I noticed that he was doing more unique character voices for this book. It was largely fine, though a bit odd since the narrative structure of the series has Dresden relaying the story to us (in other words, it's not Murphy speaking, but Dresden telling us what she said), so the individual voices don't really fit in such a context. But that's easily overlooked and not very important. The problem I had in this book is that a few of the voices, Mrs. Spunkelcrief (Dresden's landlady) in particular, were very jarring. In her case, the voice sounded sufficiently like Mickey Mouse to put the audiobook production team in danger of a trademark lawsuit. It was only for a small handful of characters, and they were characters who got very little narrative time anyway, but I found it off-putting. 
 To wrap up, I thought the book was great, and it really shook things up and I look forward to seeing how the changes play out in the next book.