Aside from his terrible title pun, the psychologist and media consultant David Jennings is a very smart man, and his book Net, Blogs and Rock 'n' Roll should prove valuable to anyone interested in how people are discovering, and will discover, new music and other media as the digital age progresses. There's a lot of talk these days about celestial jukeboxes, long tails, folksonomies, the tearable web, "some rights reserved," and other modern concepts in arts, marketing, and commerce, but Jennings has pulled them neatly into a sensible, readable package dense with ideas and reflecting a very positive outlook.

The internet has enabled us to easily find virtually anything we want. Hence we have, as Jennings says, "what fans used to dream of... Our problem now is scarcity of attention." The book details what entrepreneurs and thinkers are starting to do, and might yet do, to try to capture and focus the attention of consumers and fans of music, movies, videos, etc., and the new ways in which those fans, through technology and community, are "foraging" for their media sustenance.

I deliberately used both terms, "consumers" and "fans," because as Jennings makes clear through the use of a pyramid concept that will probably look familiar to marketing managers, there are four types of music listeners: Savants, Enthusiasts, Casuals, and Indifferents. People in these different groups discover new music in various ways. "While Savants [people for whom music is an essential part of their identity, and who often play a creative or leadership role among fans] and Enthusiasts may choose their friends based on what music they like, Casual listeners are more likely to choose their music based on what their friends like."

The pyramid can also be expressed (top down) as Originators, Synthesizers, and Lurkers. But either way, "communities do not require majority participation in order to be successful and to generate content and relationships that their members find valuable," and a "cycle of influence" among these groups "can significantly affect the word-of-mouth reputation of a book, film, piece of music, or game."

Jennings explains the difficulties and the potential for "gatekeepers" who try to generate meaningful popularity "charts" in a context where means and opportunities for distribution and consumption are very inconstant. He also talks about the changing roles of intermediaries like reviewers (in the age of blogs), editors (Last.fm doesn't have them; the All Media Guides do), and human and automated "DJs." Regarding the last, Jennings makes the important point, in a chapter called "Cracking the Code of Content," that "The power to program becomes more important as the range of material available to us on demand keeps on growing." We use music in a variety of ways - active listening is only one of them - and we have an expanding number of technologies and techniques we can employ to discover music and program personal playlists.