As my FP colleague Isaac Stone Fish, Bloomberg View's Adam Minter, and others have very ably documented, China's microblogs have been buzzing all week with rumors - unsubstantiated -- of a political coup in Beijing. (Were those gunshots you heard? Oh, just fireworks, as per the usual in Beijing.)

Ironically, this latest eruption of China's online rumor mill has happened shortly after the government's plans to enforce real-name registration and other controls on Weibo -- the most-prominent Twitter-like microblog -- went into effect. Or were supposed to. Although Ai Weiwei's real-name Weibo account was quickly deleted, other lesser-known users report myriad workarounds: You can verify your identity with an SMS message to a phone that isn't actually yours, for example. One couple reports that the Weibo account they set up a while back in their dog's name is still as barking active as ever. (The dog, for the record, had no comment on coup rumors.) While it's too early to say if enforcement of polices -- or penalties for political chatter -- will be stepped up in the future, evidently Beijing's new controls have so far done little to dampen online speculation and conversation.

Stepping back, this has been quite a year for Weibo. From rumors of Jiang Zemin's death (not true) to rumors of chemical-spill havoc in the northern city of Dalian (highly exaggerated) to rumors of tanks this week in Beijing (not true), we've seen how quickly fear and speculation can spread over the microblog.  Meanwhile Weibo has also been a venue for important and legitimate watchdogging, including calling out government lies about the causes and impact of the Wenzhou high-speed train crash last summer, arguably pushing the mainstream Chinese media to be more aggressive in reporting as well. But there's something else all these examples have in common: Scratch just below the surface, and it's easy to see how readily people in China, or at least those inclined to discuss politics on microblogs, assume the government is lying to them.

Most of the time, the authorities' reaction is to censor key terms -- like Jiang Zemin or Wang Lijun (the name of Bo Xilai's former deputy) -- which actually seemingly gives more credence to the chatter (what are they really hiding from us?). In the case of high-level political rumors, there's no authoritative government source that ever comes forward to clear the air; as The Globe and Mail's Mark MacKinnon memorably wrote on his blog: "And now I'm passing on the scuttlebutt too. Why? No one in Zhongnanhai is taking my calls. They're not taking anyone's calls - which leaves the outside world in the dark at a crucial moment in Chinese history." Even when government officials try to offer denials through state-run media -- as in the case of pollution fears in Dalian -- they aren't often believed. As one woman who participated in the Dalian protest last fall told me: "We feel hopeless about our local media."

The only way to really crush rumors over time isn't by trying to nickel-and-dime manage microblogs; it's by establishing some channel of trust to mediate between truth and falsehood, between the smoke-filled chambers of government and the people. Rumors can take off in any country, but they have special potency in China because there's no equivalent of a trusted Peter Jennings or White House news conference to vet before the public what's real and what isn't. And so in a city already on edge, fireworks sound like gunshots indeed.