It is hard to pull the same trick twice. Apple nicked the music market from under the noses of record labels by adding the iTunes store to software running iPod music players. The video industry, however, is forewarned and forearmed. Already running several experiments, including online video site Hulu, and a variety of video-on-demand trials, Apple will not be stealing a march on a declining industry this time.

For Apple, talking to broadcasters about Apple TV participation appears to be part of preparations for next year's launch of a tablet device, somewhere between a phone and a laptop. Offering a monthly Apple TV subscription could spur demand and be a natural evolution from Apple's existing download service.

Meanwhile, for the national free-to-air broadcasters such as CBS, a deal with Apple could be part of a broader negotiating tactic in the battle over retransmission fees. Now that 90 per cent of households receive television from cable or satellite providers, a high fee per subscriber from Apple would help the broadcasters' argument that they deserve more from other distributors.

The danger of internet TV is that it cuts into advertising revenues because online viewers tolerate only a few ads, while subscriptions or downloads may eliminate them entirely. But the age of online video is still far off: the average American watches just two minutes per day, according to Bernstein Research, compared to six hours of live TV. Cable companies could even turn out to be surprising winners if internet TV really does take off. They do become dumb pipes. But most areas of the US only have two choices of broadband provider and cable networks' infrastructure is superior to the telecom operators. They would keep their customers but see the half of their capital spending bill devoted to set-top boxes disappear. That would be quite a trick.