Count them: more than 550,000 people have signed The Sun's petition demanding that Haringey council sack the social workers involved in the wretched case of Baby P. That is more than ten times the number who formally complained about Russell Brand and Jonathan Ross, but no council employee has yet resigned, while several from the BBC have gone.

Even an apology from Haringey's leader took more than a week in coming when the story emerged after a court hearing in the case where a baby died in August 2007, as opposed to people swearing into somebody's answerphone. One can only wonder at what level of support an online petition must reach before the council - a Labour council - will actually take some firm action in response to the public mood.

What The Sun petition shows is that although the media dynamic is changing - the internet makes registering a protest a matter of a few clicks, rather than knocking on hundreds of doors - it is the mass media that generate the impulse to complain. Which is why, of course, there were two complaints immediately after the Russell Brand broadcast, and tens of thousands once a combination of newspapers, starting with The Mail on Sunday, and BBC News highlighted the issue (in the case of the latter, repeatedly).

Complaining to Ofcom about any offensive programme via its website is a matter of a few clicks, too. But if the complaints to Ofcom are a by-product of media coverage, the Baby P petition shows that a sense of public anger can be harnessed directly by a newspaper, too.

These activities reveal the power of the digital mob - one that, if anything, is growing in intensity. It is public sentiment crystallised into tens of thousands of clicks and stimulated by television and newspapers - and which perhaps first emerged during the Celebrity Big Brother affair.

This is seen not only in rows about television but in the millions who checked their bank accounts in the wake of government agencies losing child benefit data.

It is also seen when tens of thousands of people who switched their deposits, most likely minutes after watching Robert Peston on the news, from the weak banks to the strong ones. That contributed to the sudden collapse of some of Britain's most powerful institutions. And the mob votes for Rick Astley to win awards for greatness, in defiance not only of many people's taste but also of the former chart-topper's wishes.

Stay in tune with the mob and it is a force that can create a virtuous feedback loop. One minute John Sergeant looks amiably goofy, then, as the public keeps voting for him, he becomes a national hero, fêted in newspapers to the point where he looked well placed to win Strictly Come Dancing - well, until he quit this week. The BBC will not say how many voted for him but one suspects that the numbers are high - if only because X Factor voting is also running at record levels, as if the phone-in scandals had never happened. Mind you, as a former political journalist who was shoved aside by Margaret Thatcher in her last moments in office, Sergeant was smart about his timing, sensing perhaps that at some point the mob can turn.

It is also a trend, though, that should be disconcerting, particularly for anybody exercising power. The new volatility is demonstrated when politicians can go up and down in the polls with remarkable speed. The sudden crises change perceptions and shatter received wisdom, whether in the failure to call a general election or in the fallout from a summer trip to Corfu.

Make a mistake on television and perhaps in other media, too, and the public response will be swift - and it is not obvious that any organisation can resist once the storm whips up. Considered inquiries and gradual decision-making of the kind that regulators such as Ofcom specialise in barely look credible, even if there is a need to establish facts in the pursuit of justice.

But it is also a force that newspapers - which have the freedom to take a political line - can direct. At a time when the commercial underpinnings of the newspaper business have never looked so fragile, it is curious how the power of print over audiences is as strong as ever. The numbers signing up to The Sun's petition demonstrate that.

— Speaking of commercial underpinnings, whatever you do, don't think about January. National newspaper advertising was down about a tenth in October at most titles - about the same as seen in broadcast television - and nearly 30 per cent in regional newspapers. But the question is what happens when the retailers, who seem to be starting their January sales already, rein in spending in the new year.

It does not help the newspaper business that the cost of newsprint is likely to rise about 20 per cent in the first month of the year, which is why owners have been queueing up to announce layoffs now. The hope is that the picture will brighten a little from around Easter, but as the weather gets colder, spring seems to be a very long time off.

dan.sabbagh@thetimes.co.uk

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