So who is in the frame to replace Heggessey as BBC1 controller? Accused of being too populist, she nevertheless leaves on a high. But her successor faces testing times, reports Steven Vass

"She revived Saturday nights, " says Colin Cameron, Scottish head of independent production company Lion Television and a former senior BBC manager in Scotland and London.

"She allowed quite a bit of growth and development in areas like drama and entertainment, which were perceived before she came along to have gone off the boil."

Harry Bell, creative director at Tern Television, agrees.

"She's tackled every genre with a lot of success. The audiences have borne that out."

More controversially, BBC1 overtook ITV1 in the ratings in 2001, her first full year in charge, and has generally stayed ahead since. Admittedly, this was assisted by several quirks of fate. ITV was floundering at the turn of the decade as ITV Digital went under and the advertising downturn squeezed its budgets.

And Heggessey was playing lieutenant for most of her tenure to Greg Dyke, a director general whose background with commercial broadcasters TV-AM and LWT gave him an impetus to compete with commercial channels.

Furthermore, her budget benefited from a hike in licence fees well in excess of inflation.

All the same, Heggessey gave critics plenty of ammunition for populism-bashing. As well as shifting back the night-time news, she moved Panorama to a late-night Sunday slot; stuffed the schedule with extra Eastenders, Casualty and Holby City;

and commissioned me-too shows like Fame Academy.

Ironically, her problems were at the populist end of the schedule: Johnny Vaughan and Denise Van Outen's Passport To Paradise, Dom Joly's World Shut Your Mouth and, arguably, Michael Parkinson's move to ITV1.

Heggessey did lure Graham Norton from Channel 4 to BBC1, but a year into the multimillion pound deal he has yet to make a programme, reputedly over a failure to agree on the format. Meanwhile Eastenders's 20th birthday probably marks the ropiest time in its history, with ratings well behind Coronation Street and sometimes scraping six million.

But what the critics of dumbing down miss is that populism has been out of fashion at Television Centre since Dyke's departure in the wake of the critical Hutton report early last year. Under successor Mark Thompson and chairman Michael Grade, the BBC has adopted a much more public service tone, no doubt partly because the government is due to renew the BBC's Royal Charter next year.

Heggessey's rhetoric has followed suit, not least in a Sunday Herald interview last summer, when she was keen to play up things like Children in Need events, highbrow documentaries and Test The Nation.

As she put it at the time:

"There's been a change of emphasis rather than a change of strategy. It's not like we didn't build public value before. What we are trying to do now is draw everybody's attention to the huge amount of things we do."

The BBC's journey through more sober waters has continued since then, with Thompson announcing budget cuts in December to improve the value of services. In view of rumours that this has destabilised Television Centre, and the fact that Heggessey previously said she wanted to stay on several more years to become the longest-serving controller of BBC1, there have inevitably been suggestions that she jumped - or was pushed.

"I don't think it's anything as clear cut as her falling out with Mark. But the period she was there was an expansionist one, and it is easier to do these jobs when there is money flowing, " says Cameron.

"Clearly that's not going to be the case as Mark gets [the BBC] back on to a proper financial footing. It was a smart move to get out when she was perceived to be doing well, " he says.

Paying too much attention to testing times at the BBC also overlooks the fact that she is leaving for Talkback Thames, the independent production company behind shows like Bo Selecta! , How Clean Is Your House, Never Mind the Buzzcocks, Da Ali G Show and I'm Alan Partridge. It is thought to be the first time a BBC executive of her level has made this kind of move.

Along with rivals like Endemol and RDF, it is one of the new generation of "superindies", which have grown out of a 25-year government policy of strengthening the sector.

"It's a sign that the indie sector has matured that there should be a migration of this sort from a large broadcaster to a large indie, " says John McVay, chief executive of independent producers' association PACT.

"The independent sector is less risky nowadays. The business models look a lot more robust than 10 or even five years ago, which makes it more tempting for someone like Heggessey to jump ship."

Given that the government is almost certain to raise the quota of BBC programmes that have to be made by independents from 25-per cent to 50-per cent for the next 10-year charter, which commences in January 2007, Heggessey's successor will have to make increasingly difficult decisions to farm out in-house staples.

The public service theme is also almost certain to continue.

Harry Bell believes BBC1 will follow the BBC2/BBC4 trend under Thompson of becoming "much more cerebral, specialist and focused on informing", although "it will still be a big entertainment broadcaster, will still appeal to big audiences and will still take ITV1 on".

On the day after her departure announcement, the BBC promised a pounds-3m hike in annual current affairs spending in response to a report from the governors criticising BBC1 for being weak compared to ITV1.

There is neither a time scale for when Heggessey will leave, nor an heir apparent. Alison Sharman, head of daytime, is highly regarded but possibly too inexperienced. The same may be true of Dan Chambers, controller of Channel 5 and Stuart Murphy, controller of BBC3.

Jane Tranter, head of BBC drama, is presumed to be a front runner, with commissions like State of Play and Blackpool under her belt. But she lacks the experience in factual programming conventionally required for the job, and her young family might make it difficult to persuade her to take it on.

Another is Kevin Lygo, director of programmes at Channel 4. He is known to be admired by his former boss Thompson, but there are rumours he is being groomed for Jana Bennett's BBC head of television post.

There are no Scots on the list. "There are Scots in important television jobs in London, such as Alex Graham (head of Wall To Wall Television UK) and Graham Stewart (co-head of So Television with Graham Norton), " says Bell. "But they are doing perfectly well in the indie sector."

Cameron says: "Nigel Pickard [director of programmes at ITV] is the person I would like to see doing it. He's a great commissioner, a great producers' person and understands programmes.

But I doubt he will go for it - he doesn't relish a high-profile role and he's doing a fantastic job at ITV just now."

He adds: "There is probably someone we haven't thought of yet. Someone that Mark or Jana is going to have a quiet word with."

CONTEXT

Lorraine Heggessey's announcement last week that she was standing down as controller of BBC1 to head up Talkback Thames throws open one of the biggest jobs in television.

While she is linked with fierce commercialism, her successor will have to make public service and value for money the top priorities.