The Chinese equivalents to YouTube and Amazon made "spectacular" debuts on the New York Stock Exchange last week, each doubling their value within hours of going on the market. Youku, a video-sharing website, almost tripled its $12.80 offering price to end its first day of trading above $33 a share. Online retailer Dangdang doubled its value after 24 hours of trading. But the astonishing success of Chinese IPOs like these — which make up 35 percent of the total new listings on the NYSE this year — has some hearkening back to the dot-com days, when the market invested billions in tech firms only to watch their stocks plummet back down to earth. Could this be a new bubble, and should investors exercise caution?

These Chinese firms are a bad buy: "What's going on here?" asks Gady Epstein at Forbes. The U.S. stock market has poured billions into Youku, despite the fact that "no one pays to watch its videos, there are very strong competitors and, oh, it is still losing tens of millions of dollars a year." U.S. investors "desperate for a pop in their portfolios," are swooning "irrationally." Your Chinese "word of the day" should be "paomo" — yes, that means bubble.
"China IPOs: How do you say 'bubble' in Chinese?"

Analysts are too paranoid about bubbles: "Name an asset and there are worries that it may be a bubble in China," says Paul R. La Monica at CNN Money. But while there have been outstanding "individual success stories," the Shanghai market as a whole has "taken a big hit this year." And some investing pros say concerns about the Chinese tech, real estate, and commodity sectors may be "overblown."
"China is hot. But is it too hot?"

Bubbles can be profitable, too: The return of "one-day IPO doubles" can only mean one thing, says Jon Markman at MarketWatch: The "return of the bull market to Wall Street." Even though it's common knowledge that "the market suffers from fads when money is loose," there's no reason why you shouldn't enjoy rewards if you're sensible and get out while the going's still good. Remember, "bubbles are only bad when they pop."
"Welcome back, bull market"