Some say the difference comes down to American media's reliance on television. TV spending is expected to top $72
billion in the U.S. this year; in Britain, there are fewer TV channels and the audience is much smaller, so far less is spent on TV. That may be why the top 50 national advertisers in the U.S. spent
just 3.8% of their budgets on the Web in the first half of this year.
Others point out that in the U.S., many Web publishers sell through ad networks, which means advertisers don't have much have say over where their ads appear--and advertisers like control, especially big advertisers. That may be a cultural thing, but in Britain, national advertisers have more opportunities to work directly with publishers, which may be why they're willing to allocate as much as 30% to 40% of their budgets to online.