News Corporation, Rupert Murdoch’s international media giant, is reportedly working on an iPad-only newspaper that won’t exist in printed form.

Murdoch’s main involvement in online technology to date has been putting some of his leading titles behind a subscription-only “paywall”, making the newspapers available to paying users only. So far that project has attracted customers but, even with the increased attractiveness of a focused audience for advertisers, it doesn’t appear the subscription fees have made up for the loss in ad revenue of shutting out the vast majority of site visitors.

The precise details of the new project vary depending on the source. (If you think journalists are gossipmongers, you should see the way they talk about their own industry.) The most consistently reported points are that it will be known as The Daily, be produced from the company’s Manhattan office, and debut in December or January.

The newspaper — if you can call an electronic-only product a newspaper — is said to have a staff of 100 and a start-up budget of $30 million. It will syndicate some content from other News Corporation titles, but most of the material will be original. Reportedly readers will have to pay either 99c a week or $50 a year, though the latter figure makes little sense as a subscription discount.

Apple’s involvement in the product, if any, appears to have been talked up through the rumor mill. One British newspaper referred to reports that Steve Jobs was a “major fan” of Rupert Murdoch, which sounds unlikely from a purely political perspective. That somehow became enhanced in other reports until it was being rumored that Apple engineers were helping out on the project to ensure not only compatibility, but that the newspaper made full use of the technology.

There are also conflicting reports about whether the publication will be available on other tablet devices. Even if that does happen, I’d expect it to come after the launch, simply because of the need to produce separate applications.

As fascinating as it will be from a technology and journalism perspective to see a title designed specifically for the iPad rather than adapted from print, for me the numbers simply don’t add up. The $30 million budget is the equivalent of 600,000 annual $50 subscriptions. Depending on how the budget accounts for running costs, that could of course be, for example, met with 200,000 customers over three years.

But even that would be 2.6% of the entire iPad audience worldwide. Take into account that 21st century newspapers traditionally aim a specific audience, either geographical or political, and it’s hard to see how — even with whatever advertising the project can raise — such a project can turn a profit any time soon. Then again, when your company has assets of more than $50 billion, such matters aren’t always a major concern.