This USA Today article covers AdSense from a lot of angles, and is worth reading. However, what caught my eye was this quote from Jason Calacanis of Weblogs, Inc.
In his first four months of Web publishing, AdSense brought in $45,000. Some of his blogs produce $3,000 a month. His best do "four figures," Calacanis says, though he's reluctant to fill in the exact numbers. "And that's with zero marketing," he says.
Maybe it's the old marketer in me, but someone who's getting their company mentioned in the USA Today is NOT doing "zero marketing". Whenever you hear that, either the company is run by engineers who are bragging that they don't need marketing, or it's run by a savvy marketer, who's pulling the old "I'm not an orator" rhetorical trick...
The point is, if you are hearing about it, and they have any web presence, they are doing marketing, whether they like it or not...