It's a blog! Mainly of book reviews.
Scalzi admits that this book arose from complaints about two plot holes in the previous volume of the series, giving us the same story from the perspective of the former protagonist's daughter. Initially this is boring because, despite a convincingly different (i.e. teenage girl's as opposed to her 90 year old father's) voice, the events described are just recapitulation. Fortunately, we fairly quickly move to significant events that we had no knowledge of from the prior book, the two major gaps in the story as told in the previous tale are well and truly filled in and we learn some more about the over-arching galactic political situation and the history of same.
If you liked the previous entries in the series you'll probably like this, as long as you get past the overly long start which adds nothing new.