A format war in consumer electronics is like the US presidential primaries: victory requires momentum. That is certainly the case with high definition DVDs. Consumers are indifferent between the Blu-ray standard championed by Sony and Toshiba’s HD-DVD – they are similar in capability if not in design – but they do not want to buy the loser and find it obsolete within a year. It now looks, however, as if this war has been won.

In DVDs, the critical momentum-building contests are not Iowa and New Hampshire, but Paramount, Warner Brothers and 20th Century Fox. Without their support there are no DVDs to play. Warner’s announcement that, henceforth, its high definition releases will be exclusive to Blu-ray means that the Sony format is now backed by a majority of Hollywood’s players.