Google abetting typo-squatting?

The Washington Post has an article this week on the typo-squatting business.

Typo-squatting is the practice of grabbing up domain names which are likely typos of well-known domain names (as an excercise, try the url "aoll.com"). The typo-squatters fill the web pages with advertisement. Enough people click on these ads to make the practice profitable.

In the Washington Post article, The Web's Million-Dollar Typos, it's alleged that Google makes millions of dollars by providing the advertisements used by the typo-squatters. Although Google does not allow trademark-infringing web sites in their advertising network, they allegedly do not enforce the policy as vigorously as they should.

The article includes quotes from noted internet anti-spam researcher Ben Edelman.