But as marketers continue to determine the return on investment for their entire online effort, content is factoring in.
Vendors usually put marketing materials online, add those costs to the marketing budget, then evaluate the budget as a whole, said George Reilly, a research director at GartnerGroup, a Stamford, Conn.-based market research company. If you can separate online costs from off-line costs, however, ways exist to calculate benefits, he said.
If you can track each user through Web site logs, "cookies" that identify personal computers anonymously or registration data, "then over time you can gather that data and learn how many members use parts of your content," Mr. Reilly said.
The word most often used by marketers to describe the content of their sites is "transactive." By that, they mean the aim of their content is to enable transactions. Content doesn't sell ads, and it's not there to be sold for its own sake.
This business model is different from that of a 101-year-old publisher such as Thomas Publishing, New York, which nevertheless has successfully moved its Thomas Register online.
"Our whole business model is that the content we provide draws the users, and the users provide a return on the investment of our advertisers," said Associate Publisher Pat Deloisio.
The Web has enabled Thomas to expand its content offerings. Its data now covers 250,000 types of industrial product offerings, and the company has 23,000 advertisers, Mr. Deloisio said.
The Web also enabled Thomas to sign an alliance with Autodesk, San Rafael, Calif., under which it has produced 750,000 computer-aided-design files on listed products for engineers to download free.
"You can put this into an existing design, and all the attributes come with it," he said. "When that's done, 84% of the time that product is purchased."
"It's all commerce-driven," said Mike Kelly, director of corporate communications for MetalSite L.P., a Pittsburgh-based exchange for trading metals such as steel. "You have to ask, 'What's the content that's most relevant to the marketplace?' "
The definition of "relevant" content will change with the information customer and the potential buyer, said Kevin Jones, editor of online newsletter "Net Market Makers", Berkeley, Calif., which analyzes the b-to-b Internet market.
For example, buyers of commodity products need to know only where the products are and what their cost may be, he said, while design engineers who are choosing chips to put in cell phones need more decision support.
Content at distributor BuyersZone, based in Boston, is also transactive. Its service "Inside Scoop" may appear to be a small-business magazine, but Online Editor Sandra Boncek said it aims visitors directly toward the transaction capabilities of the larger site.
"Business buyers can see our content as the foundation on which they make buying decisions, whether it be a photocopier or business insurance, a payroll service or a fax machine," she said.
BuyersZone isn't the only site with this strategy. To further serve its audience of buyers and specifiers, Chicago-based PlasticsNet entered a marketing partnership with Injection Molding magazine, published in Denver, said Tom Rodak, exec VP of PlasticsNet, a marketplace for the plastics industry.
Training on injection-molding machines is aimed to sales of spare parts for those machines, he said, as the site builds a market for industrial machinery, not just plastic resin.
The role of content should be evaluated differently in every market, said Mark Walsh, president of VerticalNet, Horsham, Pa.
"We now run 47 individual sites, each aimed at a distinct b-to-b community," he said. "How that specific community uses content can vary widely, and thus our business model varies."
For VerticalNet site Pollution Online, "product information is content," Mr. Walsh said. In Property and Casualty.com, an insurance site, or Nurses.com, a medical site, "it's often more service-oriented. There's less robust product content information there."
For most b-to-b sites, then, free content is specific to the market's needs, and the return is measured in terms of sales. Yet high-end paper newsletters continue to do business, charging for figures or insights that can deliver a competitive edge.
In those areas, Mr. Walsh said, VerticalNet is prepared to be a reseller. In its new high-end content plan, "you'll be able to go to Oilandgas.com and buy a high-end newsletter for that industry. We get a portion of that sale," he said.
Still, Mr. Walsh said he sees newsletters as secondary to VerticalNet's role of building business communities.