Google is testing interspersing alternate listings that appear to be commercial in nature into its natural, or organic, search results.

A recent search for "on demand," for example, returned an area delineated off from natural results, occupying the above-the-fold sixth through eighth positions in the organic results area of the page. Within the clearly demarcated but unlabeled space were three listings for Comcast services.

Mike Levin, VP of Connors Communications Interactive Group, called the listings "very commercial-looking results." He claims his company has examined 50 keywords and -phrases which, when queried, delivered similar results in the same demarcated position on the page.

"We're finding results that may be an experiment in a new system of determining relevance," Levin said, "So they are taking positions 6,7 and 8 they're drawing horizontal lines and they are doing something else in that spot. Which on its own has tremendous implications for the organic search optimization field."

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