The move to use search to advertise the end of subscriber-only content is premised on the idea that Web users already know what content they want online--news, games, video, and the like--but need help in figuring out where to find such offerings, said Ron Belanger, Carat Interactive's vice president for search and affiliate marketing.

"We're not trying to create demand here. Demand is already there," said Belanger.

Most of AOL's existing channels--ranging from the African-American-centered "Black Voices" to "Personal Finance" to "Sports"--are in the process of optimizing sites for search engine crawlers, so they'll be findable when the subscriber-only wall disappears. Belanger added that the varied content on the separate channels required individually tailored approaches. "It's not your cookie cutter search marketing campaign by any stretch of the imagination," he said.

A few AOL channels already have started using search engine optimization and marketing. AOL's music channel, for example, which became available Web-wide several months ago, put in place a search optimization/marketing plan. The optimization took almost two months, Belanger said, adding that AOL started doing keyword buys in January.

From the fourth quarter of last year to the first quarter of this year, traffic at AOL's music site grew by almost 40 percent, said Kevin Conroy, executive vice president and chief operating officer of AOL Media Networks.

A Google search Tuesday afternoon on the terms "Coldplay" and "video" returned AOL's music channel as the top sponsored listing, although there were 39 links above AOL--including links to Yahoo!'s music section, MTV.com, and VH1.com--in the organic results listings.

At the same time, AOL's entry into the keyword market for music slightly increased the cost of music-related keywords, Belanger said. "Music's gotten a hair more expensive in the last six months," he said. Still, he added, the uptick was insignificant compared to keywords in other industries. "It's not the kind of drastic increases in cost per click as we've seen with some of our other clients."

Optimizing all of AOL's channels required taking on an "evangelist role" in terms of "getting search engine optimization into the DNA of the organization," Belanger said. The effort involved making changes large and small, such as using HTML links rather than JavaScript in some cases, cross-linking between pages, and tagging images in a crawler-friendly way.

AOL also intends to buy keywords on search engines to drive traffic to its channels, with the amount spent based on a complicated analysis of return on investment. In some ways, that analysis is more complex for publishing sites than e-commerce sites, where return on investment can be calculated by looking at whether visitors who come to the site make a purchase.

"We put together live models with some folks from AOL finance that really look across what they're selling--ad rates, sell-through rates, pages consumed per visitor," said Belanger.

While it's relatively easy to calculate return on investment if advertisers are paying on a cost-per-thousand impression basis--where more eyeballs automatically increase ad revenues--evaluating keyword buys becomes far more complicated when advertisers are paying on a cost-per-action basis.

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