Jeff Vandermeer interviews M. John Harrison on "Nova Swing" at the Amazon.com book blog.
"Amazon.com: You've returned to the same setting as Light with Nova Swing, but Nova Swing isn't really a sequel, right?
M. John Harrison: It's a kind of companion piece. It's less sprawling than Light. It could be read independently but there's some interplay, which you would miss if you hadn't read the other book. I wanted to revisit the genetically-modified servants and entertainers--the prostitutes, gladiators, rickshaw girls and gun-kiddies--and show them as more human than some of the human beings. A key element I wanted to extend from the first book was the idea of human behaviour as code, further undermining conventional ideas we have of personality, character and consciousness. I liked the idea of a kind of life based on complex algorithms which can run themselves on any platform. The Kefahuchi Code is imagined as preceding physics in some way. Reality is just another substrate it can run on. "