This is a big year for China's booming five-star hotel industry.Almost 40 fivestar hotels are currently under construction in Beijing,while luxury hotel group Marriott will add three more properties in the city by the end of the year.But what is driving all this growth,and is it sustainable? Rauf Malik,general manager of the new Marriot City Wall Hotel,Beiiing,recently drew on his 20-plus years of hotel management experience in China to weigh in on the industry's outlook.