Ancillary Justice by Ann Leckie

When coming so late to a novel that has been as rapturously received as Ann Leckie's debut (it is the winner of--deep breath, now--the Hugo, Nebula, Clarke, BSFA, Locus, and Kitschie awards, was nominated for the Philip K. Dick award, and noted in the Tiptree award honor roll) there's a temptation to focus one's critical thoughts on the obvious question: why this book?  What is it about Ancillary