Note: this is the fifth in a series of blogs looking at the history and future of Web 2.0. The user-participation culture of Web 2.0 has begun to change the worlds of music, movies, animation, games and even encyclopedias, but in no area does the change promise to be as deep and fundamental as in the world of news. While other aspects of user-created content blur the line between authors and audiences, the line remains there: it still takes tremendous skill and effort to make a mashup or a fan movie, even if Web 2.0 has made those things easier to distribute. Some have suggested, though, that it will change journalism in a much more radical way – perhaps altering our idea of what journalism is entirely.