Beijing (CNN) -- Xi Jinping is a mystery. So much so that the presumed leader-in-waiting of the world's most populous nation could vanish for more than a week without any explanation being given. In September this year, Xi disappeared. It sparked a flurry of rumors: he'd had a heart attack, suffered a stroke, was injured swimming, and had even gone on strike. Xi eventually re-appeared and normal transmission was resumed. But should we be so surprised? Barely an analyst I've spoken to can say they really know him, or what type of leader he would be. Mike Chinoy, a former CNN correspondent and now a senior fellow at the University of Southern California's U.S-China Institute, has seen China's leaders come and go but concedes Xi is difficult to read.
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China preparing to bring in its next generation of leaders at its party congress
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Mike Chinoy: Xi Jinping is in many ways an unknown commodity
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Modern Chinese Communist Party is run by a small collective
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Xi will face slowing economy, internal friction and regional disputes
The @placeholder of the 21st century has no supreme leader.