From the New York Times' David Pogue:
...Google's advertising network sales, which come largely from its AdSense advertisers, reached $675 million in the third quarter of 2005, the last period for which Google reported results. That figure was up 76 percent from a year earlier. AdSense generates slightly less revenue than Google's primary revenue engine, its search Web sites, which sold about $885 million worth of ads in the third quarter of 2005, a 115 percent jump from the previous year.
...millions of small sites have not yet signed up for Google's AdSense program, which was introduced in 2002. AdSense quickly gained a following among bigger companies with an online presence, like the Weather Channel, as a way to supplement their advertising deals and populate more obscure pages with paid ads. But as more small sites use the Internet to post photos, journals and other material, the number of pages that can carry new Google ads is growing quickly...
That's what makes AdSense one of Google's most compelling long-term bets, said Charlene Li, an online media analyst with Forrester Research. "I've called Google the one-trick pony for a long time, and for the most part they still are," Ms. Li said. "But they really see AdSense as the next frontier."
...Late last year, Google also gave advertisers the ability to display graphical ads on sites within the AdSense network of publishers, as well as the ability to pay different (typically lower) prices for AdSense ads than those available on Google.com. The company will not disclose how many advertisers have joined the program - "thousands" is all it says - but analysts said marketers were quickly warming to it, thanks in part to the recent upgrades.
More advertisers, of course, mean more money for publishers, many of whom would simply not publish if it were not for AdSense, Ms. Li of Forrester said. "Before, if I wanted to put advertising on my site, I'd have to hire ad salespeople, process orders - there's no way," she said. "This has taken away a huge barrier in publishing and made it viable for people to make a couple dollars, or thousands of dollars."
Read the whole article here.