New Arrival: Carnival, by Elizabeth Bear

Just in is the new novel by Elizabeth Bear, Carnival. On a far-future Earth, the population has been reduced to a few million by ecoterrorists and artificial intelligences. A pair of Earth's diplomats is send to a colony world which seemingly possesses the secret to a mysterious clean power source, which should help humanity escape the yoke of their AI rulers. What they discover, however, is an even more unexpected secret.

You can learn more about Elizabeth Bear and her books at her website.