And, finally, Dyke aims for news at eight

Tuesday's announcement by the BBC's chairman, Sir Christopher Bland, that the corporation's governors had agreed to accelerate the planned rescheduling of the main evening news bulletin from next autumn to next week certainly had surprise value. The speed with which Greg Dyke persuaded the governors - and his new controller of BBC1, Lorraine Heggessey - to swallow the switch ensured that politicians and ITV rivals were caught on the hop. Both groups cried foul, but were powerless to prevent the decision, resulting in a coup for Mr Dyke. As of next Monday, after 30 years, the Nine O'Clock News will be no more. But where does the shift leave the viewer?

Tuesday's announcement by the BBC's chairman, Sir Christopher Bland, that the corporation's governors had agreed to accelerate the planned rescheduling of the main evening news bulletin from next autumn to next week certainly had surprise value. The speed with which Greg Dyke persuaded the governors - and his new controller of BBC1, Lorraine Heggessey - to swallow the switch ensured that politicians and ITV rivals were caught on the hop. Both groups cried foul, but were powerless to prevent the decision, resulting in a coup for Mr Dyke. As of next Monday, after 30 years, the Nine O'Clock News will be no more. But where does the shift leave the viewer?

As with so many decisions, the results may take months, even years, to become clear. The BBC certainly has some strong arguments for the move. A 10pm bulletin makes perfect sense for several editorial reasons: the Ten will be able to cover Commons divisions live, and will be better positioned to cover US stories. It will segue neatly into Newsnight, allowing viewers to follow straight news reportage on BBC1 with analysis on BBC2. For the first time, news gets a fixed slot on Sunday evening - as does the current affairs flagship, Panorama. And, Sir Christopher argues, it will rebuild audiences for BBC1 news after years of decline. On this crucial point Sir Christopher is suitably vague, insisting that the new slot will attract more viewers not than the Nine currently does, but more than it would have done were the decline to continue unchecked.

But there are some strong counter-arguments. In deciding to go head-to-head with ITV's revived News at Ten, the BBC is clearly endangering its public service remit. The shift was a short-term stunt, aimed at rubbing ITV noses in their current embarrassments over News at Ten. It is astonishing that the governors allowed it to pass so easily. In hurting ITV, the governors also risk hurting the audience for Radio 4's programme The World Tonight, and all those viewers - particularly the elderly - for whom 9.30pm was a convenient getting-ready-for-bed time. For them, 10.30 is too late. But the wishes of this distinctly "uncool" audience must be subservient to the demands of a younger generation, uninterested in news. News junkies, Dyke's allies argue, are "super-served" anyway. It is time, they claim, to offer something to the millions of viewers who switch over from BBC1 when the news begins.

For despite the protestations of Sir Christopher, this decision has little or nothing to do with screening news at 10pm. It is about clearing the schedules for entertainment at 9pm. We can expect few live Commons votes, even fewer US stories that the Nine could not have handled. These arguments carry little weight. Like so many BBC bosses, Greg Dyke appears to think of news as a millstone forced on him by the BBC's charter. One need only compare his obvious enthusiasm for Match of the Day and Walking with Dinosaurs with his grudging praise for the Nine to understand that Dyke is no news obsessive.

And don't think that the Ten is the end of the shunting of news. Many BBC insiders fear that it is only the first part of a two-stage process. It is widely believed that if - or when - audiences for the new Ten are disappointing, Dyke has another suggestion up his sleeve: moving the news to 8pm. This would bring BBC1 in line with the US networks - but it would create an immediate anomaly. Why should BBC1 show news at 6pm and 8pm? Of course, Mr Dyke will point out, the solution is to drop the Six. It has never been popular among BBC1 controllers that the channel carries two evening bulletins. A single news at 8pm would free the entire network for entertainment from 8.30. If this is Dyke's long-term plan, then it certainly has a logic to it. After all, the argument goes, when in 2006 or so the vast majority of viewers can access roundthe-clock BBC bulletins on the digital channel News 24, why should BBC1 not rationalise its news coverage?

Logical, maybe. But unacceptable. Never mind the width of audience share, feel the quality of the output. The BBC has an obligation to show regular news bulletins on its primary channel. The corporation's news and current affairs coverage is unrivalled. Let us hope that's not about to end.