Future Media/Viral Media

When a video posted on Youtube gets twice the viewing audience as a nationally syndicated TV sitcom show you can be sure that the big networks are paying attention to viral media. It costs about $2.5 million dollars an episode to produce one thirty segment of a television series and it typically takes most of a year to build an audience. A back yard video shot on a $600 digital video camera should not be able to generate more viewers than the networks can get throughout an entire season - but they are. What makes media go viral (a video, a new band, a photo, a web site, etc.)? Should people who want to communicate learn how to infect the public with a media virus or treat the whole idea like a plague?