1. A per capita GDP similar to such luminaries as Jamaica and Thailand, ranked #93 in the world.
2. Epic poverty:
Live less than $1.25 a day 13.1% (172 million)
Live less than $2 a day 29.8% (394 million)
Live less than $2.5 a day 39.9% (528 million)
Live less than $4 a day 62% (821 million)
Live less than $5 a day 71.6% (948 million)
An estimated 200 million people in China are homeless. Estimates tend to be conservative, and there will be many more in awful accommodation which can hardly be counted as homely.
3. Artificially stimulated GDP growth: there are entire ghost cities of empty apartment buildings with prices kept artificially high in a bid to at least maintain GDP growth, when in fact many of the goods and services contributing to these figures are neither needed nor wanted, hence not worth even remotely close to what they are claimed to be.
4. A crappy language: Mandarin is highly inefficient, takes ages to learn, and is worthless, since the only moderately well-off places in China are in big cities and generally speak good English. The opportunity cost of learning something like Mandarin is enormous.
5. A super high savings rate: seemingly an asset, the savings rate is a result of Chinese households recognizing that there aren't really social programs to prop them up in the event of disaster (the way some want it in the States), plus a conscious decision by central planners to pursue an export driven growth model.
The result is an unsustainable situation in which export-driven growth needs to be replaced with more domestic consumption, something it isn't clear the central planners will be able to pull off. Failure will in all probability lead to significant, possibly fatal social unrest (see (2) above) while success will mean significantly lower growth rates, quite the dilemma.
6. A largely unproven, shite military with low quality equipment and little R&D spending, plus an embarrassingly small class of the sorts of naval vessels that allow power projection abroad (read: ONE), a necessary but not sufficient capability for any superpower:
7. An overtly authoritarian model of thought control that stifles excellence in intellectual pursuits and thus technological/scientific advancement:
Ireland has more nobel prize winners than China (9 vs 8; US=338), and China is known to imprison its own winners (see: Liu Xiaobo).
But yes, they are going to supersede the US and become a world superpower very, VERY soon. Say hello to your new overlords!