In signing up Paris Hilton, the socialite and media personality, YouTube has made a smart move. YouTube runs a fast-growing website that lets the public share video clips; Ms Hilton is a specialist in home video. Their deal, to promote Ms Hilton's debut music album, and Sony's $65m (£34.4m) purchase of Grouper, another video-sharing site, shows how quickly online content sharing is entering the mainstream. Its growth has implications for media companies both old and new.

A generational shift is under way in the consumption of media. Hours spent watching television and reading newspapers are in decline, particularly among the young; hours spent surfing the internet are rising in proportion. Ms Hilton, whose output spans movies, television, music and books such as Confessions of an Heiress, carries on oblivious. For the internet may be a new form of media but, equally, it may just be a better way to distribute the same content. Web surfers still read written words, watch moving images and listen to music. In fact, now that they can do so at work, they have probably increased consumption all round.