Apple's share price took a plunge last week, after rumours that Steve Jobs had suffered a heart attack spread online. And now the US Securities and Exchange Commission is investigating the 'reports' and their effect on Apple's stock, bringing the concept of citizen journalism under fresh scrutiny.

As if stock-market scrutineers and investors didn't have enough to deal with right now, add 'idiot bloggers' and 'gullible fools' to the list.

The Jobs heart attack story first appeared on CNN's blog news site iReport. 'Citizen journalist' Johntw wrote that Jobs had been "rushed to the ER" and had suffered "a major heart attack". iReport published and hung the consequences, as is the nature of a citizen journalist site.

The poster said he had gleaned the news of Jobs' putative heart attack from a hospital insider who was, quote, 'quite reliable'. Quite eh?

Insanely (not so) great

Naturally, the posting was entirely unreliable and insanely popular.

The only genuine threat to Jobs' well-being was the 11 percent crash his Apple shares took upon the 'news' hitting the blogosphere, no doubt almost turning the heart-attack nonsense into a self-fulfilling prophesy.

Myriad other blogs took the story and ran with nary a thought for, you know, facts. Those traditional news outlets that looked for confirmation quickly discovered the story was nonsense. Amateurism may be a glorious English tradition, but there's still room for the hard-bitten pro, it seems.

Any suggestion of instability at the top of an organisation of Apple's size - run by a leader of Jobs' charisma - is bound to hit investor confidence. And so the SEC is going to investigate, to make sure the story wasn't published maliciously with the intention of driving down Apple's stock-market price.

The rise of citizen journalism has been one of the phenomena of the web. No major news story is complete without on-the-scene-images, video and reaction from Johnnies on the spot with a steady hand and a yen for immortality. Not convinced? Think tsunami, terror attack or flood, and the images you've seen are almost certainly derived from Joe Public.

But here's the thing - reaction, footage and colour. Good. Publishing made-up stories? Not so much.

If we all want to be citizen journalists, and the evidence suggests we do, it's probably worthwhile employing at least one cynical old pro to sift the news from the nonsense.

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