Its study suggests that although "active" web users make up only a small proportion of online population, they are increasingly dominating public conversations and creating business trends.

More than half of the Internet users on the continent are passive and do not contribute to the web at all, while a further 23 percent only respond when prompted. But the remainder who do engage with the net — through messageboards, websites and blogs — are helping change national conversations, say researchers.

"We’re seeing this growing," said Julian Smith, an online advertising analyst with Jupiter Research and author of the report. "The strongest part of their influence is on the media: if something online suddenly becomes a story in the local press, then it matters."

Although unprompted contributors are generally younger and more vocal than the wider online population, they are increasingly important as opinion formers and trend-setters. Mr. Smith says businesses, media organisations and advertisers reading blogs should be wary of making assumptions about their wider significance, but that their muscle cannot be ignored.

"They’re not representative of the larger audience, but what they’re saying does matter," he said. "It’s a good straw poll — a snapshot of the verbal conversations going on that we can’t measure."

"That’s exactly right," said Glenn Reynolds, author of An Army of Davids, which explores the explosion in web punditry. "Bloggers and blog-readers are ‘influentials’ — the minority that pays attention to events outside of political and news cycles. They also tend on average to be better off, better educated and, more importantly, employed."

There are now more than 35 million blogs around the world, according to search engine Technorati. While most bloggers only write for small audiences, they can sometimes achieve wider fame or become the focus of consumer campaigns.

Companies like McDonald’s, lock manufacturer Kryptonite and computer firm Dell have all fallen foul of Internet buzz in recent years. Because search engines like Google can allow grassroots campaigns to become highly visible, industry insiders agree decisions can be shaped by a small number of activists.

"It’s always been the case that vocal minorities are listened to by media organisations, brands, advertisers and marketers — normally because they’re thought to represent a wider swath of opinion," said Tom Coates, a technologist with Yahoo! and prominent blogger.

"TV and radio programmes are censored or pulled on the green-inked letters of a few hundred people, products removed from shelves because of less than 100 complaints.

"On that basis, these figures start to sound like a pretty large number of people, and probably a much more representative sample than perhaps before."

Mr. Reynolds admits the idea of small groups being able to pressurise wider decisions is nothing new, but those who ignore online buzz do so at their peril: "You can bury your head in the sand, but very quickly you’ll look like a very old-fashioned company." (GUARDIAN)