Word-of-mouth holds most clout

For the ZenithOptimedia research, a “contact clout factor” scale of 1 to 100 was used. Word-of-mouth scored 84, compared with TV ads (69), the Internet (67), magazine ads (60), newspaper ads (55), outdoor ads (45), radio ads (42) and Internet banner ads (41).

Word-of-mouth, or viral/buzz marketing, is a powerful influencer, but something that marketers are finding hard to both generate and measure. It has evolved from recommending a restaurant to your work colleague into media such as blogs, websites, email, forums and social networks.

"The sea change is that for 40 years marketers knew that word of mouth was important, influential, pervasive. But they saw it as something to be described and hoped for," said Lawrence Feick, professor of business administration in the University of Pittsburgh's Katz Graduate School of Business.

"It is only in the last 10 or 15 [years] that they have thought about it as a communication tool that can (at least in part) be managed."

Tags: viral marketing, word-of-mouth