News: Web ads watch the clock instead of clicks
Sessions are just one of many new online ad formats bubbling up to lure reluctant advertisers to spend money on the Internet. But online ad experts said the sessions may push advertising out of a rut by recasting the way publishers and advertisers price Web ads and measure their success.

More than changing shape or style, the new format touts the measurements traditional advertisers have come to feel comfortable with in print, television and radio. Known as "reach" and "frequency," they refer to the audience an advertisement reaches and the amount of time people see it.

Such measurements are also common in brand advertising--the Holy Grail for Internet publishers hoping to tap the budgets of major consumer packaged-goods advertisers.
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