So much to say, so little time! (I'm going to try make this concise, for once, but I'll still cover as much as I can)
First, everybody who has been saying China is not a superpower is completely correct, China's military is nowhere near that of the US's and theres absolutely no indication that the Chinese are looking to confront the US. The most telling thing of all is the fact that China's nuclear arsenal basically hasn't changed all that much in forty years, and I think nuclear arsenals are by far the best indicators of military power and overall geopolitical aspirations for a country like China. So two things, China is not a superpower, and while China is a military "threat" on paper and a possible scenario, I think its highly unlikely.
Also, be careful not to daemonise China, indeed I think the biggest stumbling block against China internationally is just misunderstanding and xenophobia, a relic from the Mao years when people (actually) knew nothing about China. Most of China's big critics (including those on this thread) probably know nothing about China, indeed if you're going around talking about slave societies then you certainly don't. Cheap manufacturing is a product of both a huge labour market (due to the number of peasants coming out of poverty every year) and lower wages that is seen in all other similar GDP PPP countries. Besides, cheap manufacturing, which some people are attacking as "slavery", is the exact thing that brought Japan and the Asian Tigers to the pinnacle of modernity. The other thing people have to realise is that despite political and media restrictions, the lives of most Chinese are basically akin to the lives of people in 1950's and 60's Japan, which was in a similar state.
As for the Chinese economy, I highly doubt it will crash due to the fact that China's full potential in terms of capital has just not been reached yet, its still in the stages of modernisation. What I would like to offer is a sort of twist on what BigLutz said earlier. The analyst quoted is absolutely right that China will end up producing far more manufactured goods than it can sell, but only if it continues along its current path, which it obviously won't. The thing people really often neglect is that the next generation of Chinese will have a far greater access to universities and jobs, and what you'll see is a gradual shift in the economy from a manufacturing base to a much more service based economy (probably with an emphasis on manufacturing though for quite some time). China's middle class is exploding (in fact there's nothing more telling than the ridiculous number of luxury boutiques opening up in Beijing and Shanghai, because Chinese women love their handbags), and this will refocus the economy just as happened in the modernisation of other East Asian nations.
Also what's with this thing about keeping China pinned down low? That's just absolutely wrong and frankly selfish, the Chinese people deserve to come out of poverty. Besides the CCP is a corrupt load of crap, but its still miles away from anything like North Korea. China is basically communist in name only, so stop calling it things like "the Red Empire of the East". I actually find that quite offensive, if not juvenile.
As for my personal take on China being a threat, may I simply propose this. China is a threat only in one way, which is this. In the past, third world nations have been presented with essentially two choices: to follow a communist, authoritarian path to development, or a western, democratic path. The vast majority of nations in the world couldn't really commit to either, because they realised communism was stupid, but their leaders didn't want democracy. What ended up was countries stuck in a total quagmire where nothing really occurred, stuck at middle income nations at the absolute best. The only countries that really managed to break out were Japan and the Asian Tigers. What China offers is an example of a third path, a way to develop economically with much smaller (but still very significant, China has come a long way) relaxations on government power than would be in the west. This in itself is a threat not to any nation in particular, but to the expansion of democracy into those nations.
Finally, I don't think the Chinese dictatorship can stand the test of time. I highly doubt civil disobedience will again be prominent in the way that it appeared in 1989 (which must always be kept in mind when discussing China), and if reform comes it will probably come from within the party itself. But the party is not a small clique of domineering oligarchs, its a huge organisation with people carrying a wide range of views (whether they announce them or not is another matter). Similar to the way that a "liberal" faction of the Communist Party in the USSR "magically" emerged in 1985, it probably won't be too long before someone similar to Mikhail Gorbachev assumes control in China, and the face of Chinese politics will change dramatically. We must not forget that 1989 showed that the CCP has huge liberal elements to it; it's those internal elements that I believe will (hopefully sometime soon) bring about political reform to match the economic reform.
