Walls come in all shapes and sizes and possess a wide range of meanings; a single wall may even mean different things to different people. But news that News Limited will, next year, place at least part of its online content behind pay walls reminds us that journalism is an endangered craft and that while journalists should be paid - certainly more - for what they do, consumers are not always cooperative.

The big news coming from Richard Freudenstein, CEO of News Digital, is that not all of the news sites' content will go behind the wall (the major centres in Australia each have a News tabloid - The Mercury in Hobart, The Advertiser in Adelaide, The Daily Telegraph in Sydney, the Herald-Sun in Melbourne, The Courier-Mail in Brisbane and NT News in the Northern Territory - with the exception of Perth, and then of course there's The Australian, the country's only general-interest national broadsheet).

Freudenstein's revelation is anchored to a mention of the Wall Street Journal (another News vehicle, owned by US-based News Corp), which charges for some content. But it is, like Fairfax's Australian Financial Review (which charges for all content online), a special-interest daily, not a general-interest one. Financial news properties have done well everywhere they are charged for online. It is the general-interest vehicles that should worry about their readership simply dropping away. For this reason, a better comparison would have been to the New York Times, which is planning to place a lot of its own content behind a pay wall, probably also next year.

Falling readership in terms of very soft page view figures is what has happened in the UK, where the News vehicle The Times lost 97 percent of its online readership when a pay wall went up earlier this year, an eventuality that prompted media commentator Clay Shirky to label the site the "online newsletter of the Tories", according to the Guardian.

"The Times has stopped being a newspaper, in the sense of a generally available and omnibus account of the news of the day, broadly read in the community. Instead, it is becoming a newsletter, an outlet supported by, and speaking to, a specific and relatively coherent and compact audience," writes Shirky.

News Corp head Rupert Murdoch will have taken the same message away from the UK experiment, and his Australian editors will be keen to ensure that their mastheads are not similarly neutered. After all, Murdoch has never made any bones about his willingness to control editorial direction, tone, and political bias. Placing The Australian completely behind a pay wall would render it a toothless tiger. With his other media interests in Australia subject to forms of government control, Murdoch will want to retain all of his options when the time comes to attack the administration at either the state or federal level.

The question remains: which elements of content will be placed out of general view? It has happened, in the UK in one case I am aware of, that an opinion-piece writer has quit a news vehicle in order to prevent his work from being hidden from the widest possible audience. If you were a journalist working at The Australian you would be very concerned, right now, about where your work would appear once the wall is erected. Would it be in front of the wall, visible to all Australians, or would it be relegated to the obscurity of Australia's very own "online newsletter for the conservatives"?