After a decade of debate and mostly idle threats, newspaper publishers may be ready to begin blocking Google from indexing their content for its search results.

Two leading newspaper publishers -- A.H. Belo, the publisher of The Dallas Morning News, and MediaNews Group, publisher of the Denver Post -- are considering following Rupert Murdoch's example by preventing Google News from indexing online content behind newly erected pay walls, according to Bloomberg.

The publishers don't plan to block Google's access to all their papers in one fell swoop: MediaNews Group CEO Dean Singleton is quoted as saying that Google News will be blocked only from the paid content at various newspapers in Pennsylvania and California, the first MediaNews properties to erect pay walls.

The free content will be open to indexing as a way of drawing traffic. A.H. Belo's plans are more tentative, but the company does plan to erect a pay wall at one of its daily newspapers in the next six months. It may then follow the lead of News Corp. and MediaNews.

Currently, Google's indexing of newspaper Web content allows users to see a headline and a snippet of content -- usually no more than a paragraph -- which newspaper publishers fear may be enough for some readers. However, they have offered little explanation of how this differs substantially from the proposed pay wall system, which would -- at a bare minimum -- have to allow readers to at least see a headline (and probably a bit more) in order to entice them into paying.

Google has long argued that it actually helps newspaper Web sites by directing traffic through its search listings. Earlier this month, Google CEO Eric Schmidt was quoted in a separate Bloomberg interview as saying the decision to block Google indexing would be a "bad outcome" for both newspapers and the search giant.

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