The Middle Kingdom (Kindle edition) is currently on sale on both Amazon.com ($9.79, originally $14.57). That’s about 30% off, so get it while the gettin’s good. No discount on Amazon.co.uk, from what I’m seeing. Apple’s iBooks store is currently listing it at $13.99 in the U.S., if you’re anti-Kindle.
Thanks to Gary for the tip. More as it comes in.
Clarification: For you ink-and-paper types, The Middle Kingdom will be released on October 18th, currently at $19.26/£10.49.