People have been predicting China’s emergence as a superpower since the days of Napoleon. He appreciated China’s potential as a world power and cautioned against waking the sleeping dragon. China’s subordination into the Western international system in the 1839-1842 Opium War and its decline as the “sick man” of East Asia for the rest of the nineteenth and for the first half of the twentieth centuries dulled, but never extinguished, the expectation that, sooner or later, China would again dominate the world.
The term “superpower” is often used loosely in popular discourse to describe anything that achieves unmatched dominance from the status achieved in international affairs by the United States since World War II. The discussion here will be better served by a somewhat more precise definition: a “superpower” is a country that has the capacity to project dominating power and influence anywhere in the world, and sometimes, in more than one region of the globe at a time, and so may plausibly attain the status of global hegemon. The basic components of superpower stature may be measured along four axes of power: military, economic, political, and cultural (or what political scientist Joseph Nye has termed “soft”).
China is not now a superpower, nor is it likely to emerge as one soon. It is establishing itself as a great power, on par with Great Britain, Russia, Japan, and, perhaps, India. China is today a serious player in the regional politics of Asia, but also is just one of several. At a broader level, in global affairs, its stature and power are growing, but in most respects it remains a regional power, complementing the cast of other great powers under the overarching dominance, however momentary, of the United States. 
Will dumping the dollar make a difference? Not likely!