Still slogging through it! Haven't seen all the threads tie together yet but I'm sure they will. It wouldn't be like Brin to sneak one of his other novel's themes into this standalone book, would it?

I figured out the twist about 50 pages ago: the races represented in the worldstones are long dead, and only live on as uploads in these stones. But I didn't twig that the "you" the worldstone species were using was singular. Wouldn't the Chinese-speaking stone that Bin is talking to have given this away?