Keep it up Mr. Scalzi!

A difficult book to be cataloged, it is not the space-opera is not a militaristic book, it's not that style. We feel that it was not written by a SF writer but by a writer of general literature. It has already been done and it gave the Sparrow-God by Maria Doria Russell (very good). It saves us through the SF writers, no details on the operation of the laser-pisto or big rocket, it works, and that's all that and not bother reading (first, who really knows how works not least an electric motor, they are people everywhere though!). But there's almost all strong themes of SF which we continue to read even when you are disappointed.

The identity (that is, when it was cloned?)

The alien (reflection of our time, here they are all there to butter us)

The political (what system of government is it possible or desirable when the issues concern the survival of Man, here we suspect a semi-dictatorship disguised in an apparent absence of stress on people).

Love (yes but this theme is everywhere, here is love beyond death ... nice).

In short we do not feel like discovery, themes are not surprising and reading takes place very pleasantly ... but it is in the old pots that makes the best dishes, keep it up sir Scalzi I found the sensations of my first readings of SF, there's a long time ...