A jam-packed guide to the high-stakes game Maney dubs ""megamedia"": an industry that computer, entertainment, software, and telecommunications enterprises are struggling to define -- and dominate. With appreciably more enthusiasm than finesse, USA Today correspondent Maney provides a once-over-lightly briefing on the technological advances (broadband networks, digital storage) which have spurred a spirited scramble for shares of a market that could prove The Next Big Thing. Getting down to business, he offers annotated lineups of the contenders in the race to furnish commercial/consumer outlets with information (or diversion) in a dazzling variety of new formats. The players range from regional and long-distance phone companies through cable TV operators, show-biz stalwarts (Capital Cities/ABC, Disney), and allied enterprises. By the author's account, there's almost as much convergence as competition in what might more accurately be called metamedia. To cite but two examples, Time Warner and Viacom (which recently acquired Blockbuster Video as well as Paramount) have both forged alliances not only with telephone companies but also with state-of-the-art concerns that could enhance their capacity to deliver genuinely interactive data, entertainment, or shopping services. Mergers, partnerships, and product breakthroughs, Maney observes, have created opportunities at a rate that frustrates the regulatory capabilities of governments throughout the Global Village. As the author makes clear in handicapping this race, he sets great store by visionary management. Among the many individuals Maney profiles are Bill Gates and Rupert Murdoch; covered as well, though, are host of less celebrated figures (such as Frank Biondi and John Malone) who could make their presence felt in the future. A wide-ranging and accessible if chaotically organized overview of a volatile field that, for all its glamorous potential, remains a work in progress.