In the US, where the PC and TV have such important roles, the mobile has become "the third screen," says Helen Alterius, from Ericsson's Multimedia unit.

"It is therefore all about television," she says. "In order to succeed, vendors and operators must have good TV solutions for the mobile."

Indeed, even though the US lags behind other Western nations when it comes to mobile adoption, it leads in mobile TV. This all has to do with how Americans consumers think about TV, says Revital Marom at Ericsson ConsumerLab in the US.

"They want yet another television screen," she says. "They don't want to miss anything, and they always want to be able to watch their favorite programs. So as the technology barriers are torn down, there is enormous potential for mobile services and also for user-generated content."

Operators on both the mobile and fixed sides are tweaking their business models to adapt to this new reality. So are their vendors.

Ericsson's collaboration with Turner Broadcasting, for example, gives mobile users access to Turner's internet and broadcast shows, such as CNN News and Cartoon Network programs.

The need for interactivity and TV is also creating a natural demand for IPTV in the US. As early as late 2005, more than half (56 percent) of Americans polled by Harris Interactive said they had heard of IPTV.

Features such as being able to select the time one watches a program and the ability to find programming that suits one's personal tastes ranked highly in that survey. So did the possibility of having an interactive program guide.