Harvard Business Review Press published The Ultimate Question 2.0 in English in September 2011. Within a few weeks, it had become a New York Times and Wall Street Journal business best seller. Over the last several months, translations have been published in a few other languages.
Here are some links to the book on sale in several languages:
The Chinese version should be published later this year. As always, you can learn more at the official book website, NetPromoterSystem.com