That's because the U.K. television market is relatively small compared to ad spending on U.S. television. According to figures from Magna Global, total U.S. television spending should total $47.7 billion this year. And online ad spending? A little less than half of that, at $23 billion in spending.

Still, online ad spending, while also battered by the recession, is still holding up better than traditional media such as television and radio, according to TNS Media Intelligence. According to its figures, U.S. television ad spending in the first half of 2009 plunged 10 percent while Internet display ads jumped 6.5 percent. While it's clear that if those trends continue, online advertising in the U.S. will one day also eclipse television spending, when that day will come is the $64,000 question.

As Advertising Age points out, the British television market has some quirks that helped it reach this milestone. For one, its largest television network, the BBC, doesn't take advertisements. Still, the U.K., like the U.S., has also been hit hard by the recession, prompting advertisers to examine the effectiveness of every dollar they spend. The result has been that many decided online advertising is able to offer more through techniques such as behavioral targeting.

According to PricewaterhouseCoopers' online advertising expert Eva Berg-Winters, that means "measurability in a period of instability."