I quite enjoyed reading this book, the writing is fast-paced and a lot of fun, with an undercurrent of humor throughout. Scalzi doesn't allow the humor to overwhelm the book however, and keeps the story tightly focused on the political intrigue and the action.
Perhaps it is only because I started this right after finishing Abercrombie's The First Law trilogy, but I felt Scalzi could have spent more time developing his characters, and providing more description in his scenes. While the story moves quickly and it is a lot of fun watching situations escalate in the novel, there are really only one or two characters that undergo anything resembling a true character arc, and one of those is only a minor character. It seems strange that the primary characters would go through so much and still remain pretty much the same as when they started.
Regardless, this is a fun book and quite enjoyable.