Here's a interesting article talking about how would UK government react to a terrorist attack in the age of social networking in the coming future:

"It's July 2012, and despite all the precautions - including the most intrusive surveillance exercise ever mounted and the detention of hundreds of suspects under draconian emergency powers - London is under terrorist attack. Social networks are buzzing with rumours and video clips of military units clad in chemical warfare suits gathering outside the Bank of England, where hostages are being held.

In the Cobra emergency room under Whitehall, officials from the Cabinet Office, the Ministry of Defence and the Metropolitan Police ponder their options. Someone mentions Mumbai 2008, when Twitter became the uncontrolled but main source of news, flooding in at the rate of 12 Tweets a second. A decision is taken to seize control of the flow of information from anywhere near the scene of the attack."

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