According to the survey of Jupiter Media Metrix , online music sales in America had increased markedly by 2001, namely: from 520% or 6.2 billion U.S. dollars; in 2001, only 1 billion U.S. dollars; and estimated annual growth of 43% over five years. Online music purchases were made through digital download or online orders. Jupiter Media Metrix estimated that online music sales were taking a market share of 7% of all music sales in the U.S. and increased to 32% in 2006.
In Indonesia, the interest community related to music can be found at musikamu.com, which provides information about singers, musicians, musical instruments, the collection of songs, artist images, fan forums, new albums, music industries, song lyrics with chords, chats, web radios, cafe information, and quizzes. The interest community associated with films covers Internet Movie Database (www.imdb.com), the site of film research; Film Wise (www.filmwise), the site of film quizzes; and MRQE (www.mrqe.com), the site of the best film study. The interest community related to games covers Gamespy, which constitutes a technology company and a leading online entertainment; and Nexia (www.bolehgame.com), which is a modified, Korean game, and the latter has the most visitors although still in beta, and they can interact like in daily life; for example, they can engage, get married, or die even though they can be made alive again. This game can perform smiles, tears, angers, sleeping, and singing activities. The average players in this game were about 800 people.
The interest community that has something to do with health care is WebMD, which contains information concerning the health itself, diseases, medical library, medicine, family genetics, symptoms, health guide, medical tests and examinations, e-health tools and clinical trials, including food and nutrition, old people, women, men, sports, fitness, and lifestyle. Besides, WebMD is also to facilitate the exchange of information, communication and electronic transactions among the participants who are interested in the health care. The best site of the interest community relating to the health care in Indonesia can be found at www.pdpersi.co.id, which provides information about medical devices, the people recovering from a particular disease, and the doctor community information about health regulation and hospital accreditation. Ar last but not least, the facility of the site is that of finding a doctor only by entering the name of the doctor who is practicing with a specialist area. In conclusion, the segmentation of interest communities is a promising segmentation in the future.