The day of reckoning for free internet content may arrive in the form of web browsers that by default block online ads, DoubleClick privacy chief Bennie Smith told ZDNet Australia (via Slashdot). He cited the growing use of tools such as Adblock - a Firefox browser extension - which makes blocking online ads simple. He said the trend is connected to "a negative vibe against advertising in general," but the web facilitates the production and distribution of such tools.

If enough people started blocking ads, Smith warned, publishers would charge for content. If a browser manufacturer were to offer an ad-blocking feature as a default option, he said, it should consider its own position as a marketer of its products and a publisher of content.

"They would be harming their own customer relationships to create a short-term, short-sighted, limited-effectiveness tool," he said. "One that they would probably end up having to withdraw from the market."