I picked up this book as part of the Humble E-Book Bundle, or otherwise I'd probably haven't bought it. And with what I know now I would have regretted it.

Some SciFi books feature a lengthy introduction, telling you how this setting came to be. Others jump right in and leave you wanting for more explanations. And a very few skip the introduction but manage describe the setting in words that have you understand everything right away. Scalzi manages the last way, by having his characters guess about how stuff works. Combine with that characters that are relatable, a marvelous fluid writing style, a nice backstory, mix well, and you've got a book that lends to re-reading and has you wanting for more (eg. [b:The Ghost Brigades|239399|The Ghost Brigades (Old Man's War, #2)|John Scalzi|http://d.gr-assets.com/books/1316729668s/239399.jpg|18279845])