David Carr writes "Why You Should Pay to Read This Newspaper?" (free sign-up req'd), a brief, surface-level exploration of the trend among Internet users to expect that all content is free. David humorously notes that his daughter is a good example of the demographic:

Like many of her age and experience, Erin gets music free, her My- Space account is free, and she can surf for whatever else she needs. She and her twin sister use the timer on the VCR to record their favorite shows and then skip the commercials, just like TiVo (except they would have to pay for that). When I recently bought the paid online version of The U.S. News and World Report's college resource, she and her sister Meagan acted as if I had fallen for a Ponzi scheme.

A few good points about the power that free radio and TV broadcasts have had in the past synch up with the articles general tone - free expands markets, draws in more consumers and is, typically, more valuable than paid content. The piece also explores why some outlets refuse to allow their content to become free on the web, which appears to have more to do with the psychology of the content writers and owners than with any logical, market-driven forces:

...Many print publications - magazines like The New Yorker, The Atlantic and The Economist, along with newspapers like The Wall Street Journal - require their readers to plunk down real money to access their contents. It may or may not cover costs, but it is meaningful revenue in more ways than one...

...Magazines that use subscription and newsstand purchases as an index of "wantedness" typically pay more to acquire readers than they collect, which makes little economic sense. But paid content addresses the issue of time poverty, the real challenge of contemporary print media. If they buy it, the thinking goes, they will read it.

As "Long Tail" writer and Wired Editor-In-Chief Chris Anderson notes in the article,

"Information wants to be free because it has become so cheap to distribute, copy and recombine - too cheap to meter. It wants to be expensive because it can be immeasurably valuable to the recipient. That tension will not go away."

I expect that this tension has many years left to play itself out before standardization for paid and unpaid content is accepted.