This is a decent story, fairly well written, and I got it when it was free. Still, I have a hard time seeing how it won the Nebula. There's nothing very new here. The story starts strong, in a world that's clearly unusual, intriguing, and a bit dark. But the story weakens as it moves forward. While interesting elements remain, the ending, meant to be startling, is a letdown. The writing is good, and the core concept is adequate (on the way to being tired), but there's nothing really special about the story overall. If you like Williams, or the story is free again, pick it up. Otherwise, I'd let it go.