For decades young people in the 18-to-34 age group have been the darlings of advertisers and marketers who yearn for greater sales and the elusive "buzz" of publicity. Young adults buy a disproportionate share of movie theater admissions, popular music recordings, and video games, and are regarded as prime targets by most television advertisers. As a consequence of this focus, Leo Bogart argues, media content itself has changed. Sex and violence have...