Amid the fall-out of a phone-hacking scandal that triggered the arrest of a string of Sun journalists, industry insiders believe The Sun on Sunday, whose launch is being personally led by Murdoch himself, looks likely to be heavier on fashion and football and lighter on the sex and scandal for which the News of the World was renowned.

Before it was ignominiously closed down last year The News of the World, founded in 1843, wallowed in muck-raking sensationalism designed to amuse and shock in equal measure.

Its fondness for page one headlines packed with puns and sexual innuendo was legendary.

A couple of its more memorable headlines included "Andrew and the Sex Slave Beast" and "My Big Fat Gypsy Divorce at Just 19."

In contrast, The Sun typically leads on more mainstream news stories with irreverent front-page headlines such as "Bin Bagged" when Osama bin Laden was killed.

David Mulrenan, head of UK press at media buyer ZenithOptimedia, told Reuters the new Sun on Sunday was likely to be a much tamer beast than its defunct predecessor.

"It's going to be a lot less salacious than the News of the World, and probably open up a lot more of the family market," he said.

He said The Sun on Sunday would go some way to filling the gap in the Sunday market, and that advertisers who pulled out last year over the revelation that the News of the World had hacked the phone of murdered schoolgirl Milly Dowler were likely to pile into the Sun on Sunday at its launch.

Murdoch penned a tweet on Thursday reflecting his optimism about the new title that boasted: "We're completely sold out for advertising!"

The speed at which the new paper is being rolled out - it was announced only six days before its scheduled first appearance on newsstands - came as a shock to rivals, advertisers and even the staff. It will launch at a price of 50 pence (78 cents), undercutting rivals. The price of the Saturday edition will also be cut to 50 pence from 60 pence.

"The key thing for them will be the audience because that is the way they make their money, they're less reliant on advertising," Alun Lucas at media buyer MEC Manchester told Reuters. "So they'll be aggressive in recruiting the readers and then the advertisers will follow."

The launch will pose a host of challenges both within the company and for rivals and advertisers, compounded by the fact it is happening at such a frantic pace.

How, for instance, will staff working across the seven-day title manage to reserve exclusive stories for Sunday in the way that the News of the World used to do, by holing up sources in safe houses or hotels for days before publication to keep them from talking to other journalists?

Should rivals respond with a cover price cut of their own, at a time when they are already facing long-term structural decline as fewer people buy newspapers?

And should advertisers commit to the new title when in reality they know very little about what it will look like?

CLUELESS

Sources within News International and media buyers who have met the paper's commercial team have suggested that with just days to go until the launch, staff are under intense pressure and working frantically to pull the paper together.

Journalists are offering stories but do not know how much space they will have or if their ideas are even wanted. Few have any idea of job roles or titles and the commercial team is struggling to articulate what the new paper will look like.

"The commercial team have been doing a roadshow to advertisers and at the start of the week they appeared to be totally clueless," one media buyer said, asking not to be named.

"Clients need to be persuaded that it's a good environment to advertise in, yet we don't know the cover price, the pagination, the editorial slant."

One former News of the World reporter said the company did not seem to have any concrete plans. "They seem to have announced the launch, made a big fuss and are now frantically trying to get the first copy out, and they'll figure the rest out later," the former employee said.

News groups including News International have been examining ways to cut costs in recent years, with closer cooperation between the daily and Sunday papers seen as one option.

In the eyes of many News of the World journalists, who have not been approached about a job on the new title, the new seven-day plan is simply a way to save money, while boosting morale as Murdoch challenges his critics with a new launch.

He shut the News of the World down in July when it was selling an average of 2.7 million copies.

Media consultancy Enders estimates that some 55 percent of the News of the World's sales have since been picked up by rival publishers, such as Trinity Mirror's Sunday Mirror or Richard Desmond's Daily Star Sunday, while the remaining 45 percent have dropped out of the market altogether.

As well as being the market leader, the News of the World was also impressive in that its readers came from a higher demographic in terms of age and spending power compared with other tabloids, making it even more appealing to advertisers.

Industry insiders believe The Sun on Sunday will also be more family- and female-orientated, with the glossy Fabulous magazine, which was previously attached to the News of the World, making a return, and a host of columnists providing fashion, money and food advice writing in its pages.

Nancy Dell'Olio, the ex-girlfriend of former England soccer team manager Sven Goran-Eriksson, will have a spot writing about style, while ex-Manchester United captain Roy Keane is writing an article for the debut edition. ($1 = 0.6383 British pounds)

(Reporting by Kate Holton. Edited by Andrew Osborn)

• A Permanent Economic Emergency