Storyline: 4/5 
 Characters: 4/5 
 Writing Style: 3/5 
 World: 4/5 
 Old Man's War achieved something that, I think, great authors strive to do: instill in the reader the angst, wonder, or delight of the characters which inhabit the novel. In Old Man's War, that instilled quality was an overpowering sense of curiosity and, later, a childlike delight in experiencing something new. Scalzi achieved that through an immensely intriguing set up and world vision. When I started Ghost Brigades, I couldn't see how that experience could be duplicated, and I had low expectations for what the sequel would achieve. Scalzi was very smart with the second in the series in that he didn't attempt to replicate what made the first successful. What he does instead is something different - and delightful I might add - with the same universe in which readers were hooked with the first installment. This is a character driven novel building on the idea of the (as the title suggests) ghost brigades. We readers of the first were already introduced to the ghost brigades in the original. If you've forgotten or if you never read the original then Scalzi obligingly fills you in; so don't worry. 
 The ending was a little sappy, I don't think Scalzi knows how to write a convincing child character, and I found the discussion and ideas on consciousness to be both shallow and wrong; but this was good science fiction. The technology, the future, the alien - all worth reading about.