I'm thinking language may be a big factor too, but I was thinking from a different perspective. From what I'm seeing on a brief search, only about 5% of Chinese people speak English. If you consider that much of Linux documentation is a) heavily command line based, b) spread across a multitude of websites, and c) commands would seem to be more prone to being problematic for machine translation, I think that combination would seriously slow down adoption of Linux in China and other countries with low English adoption and perhaps with non-Latin alphabets.