Just to add to the confusion: I contacted the Chinese embassy in London, and was categorically informed that "British Passport holders do not need any special permits to enter Xinjiang, only a regular Chinese visa". I don't doubt what you were told in Oz, bigdamo; maybe it is a different nationality thing (although, in the past, it seemed to be British and US passport holders who had "less fair" treatment when getting Chinese visas). All I can say is that maybe the rules aren't uniformly applied. Good luck with your trip though.