Another interesting piece, this time on how opinion leaders drive buzz...
Bloggers, discussion-board denizens, and social networkers are courted by marketers, who believe they build buzz that can make or break new products and Web sites. But there's growing controversy surrounding such efforts, and debate over just how much sway these opinion leaders really have...
... The notion that a small subset of individuals has disproportionate influence was formulated more than 50 years ago by academics Paul Lazarsfeld and Elihu Katz in their book Personal Influence: The Part Played by People in the Flow of Mass Communications. But it was Malcolm Gladwell's 2002 best-selling The Tipping Point: How Little Things Can Make A Big Difference that popularized the notion. Gladwell divided people into connectors, people who bring other people together; mavens, who get a kick out of passing along knowledge to others; and salesmen, who like to persuade others of the validity of an idea or product. When taken altogether, Gladwell argued, these archetypes create "epidemics" that spread like viruses throughout the population, triggering massive trends that couldn't be achieve by traditional top-down imposition of messages on the general public. The Influentials, by Jon Berry and Ed Keller, published a year after The Tipping Point, comes to many of the same conclusions.
It's critical to understand, however, that all these proponents of opinion leaders as drivers of social and commercial trends aren't talking about media stars or personalities, but about otherwise seemingly ordinary members of a community who, through accumulation of knowledge or number of connections with others, act as catalysts for change.