Several major websites have seen their Google Pagerank score drop in what is being called a major offensive against so-called paid links.

Industry news blog SearchEngineLand has recorded a massive drop in the Pagerank score of dozens of major news sites and blogs over the last days.

Pagerank is the formula Google uses to determine the order in which search results appear. It is based mainly on the number of sites that link to a URL, but also takes other factors into consideration. A link from a highly ranked website is believed to carry more weight than one from a low ranking one.

Among those seeing a drop in Pagerank scores are websites for The Washington Post, Forbes, and The San Francisco Chronicle, as well as well-known blogs Engadget, Joystiq, and The Unofficial Apple Weblog.

Many are speculating that the drops are indicative of a larger campaign by Google against the practice of selling links. Some sites have leveraged their Google Pagerank to sell links as a type of advertising space.

A Google spokesperson told vnunet.com that "our opinion of the forward links for a site" can play a role in a site's pagerank. But he also stressed that other factors also play a part in the recent changes.

If the drops are part of an effort to crush the sale of links, however, it may not pay off for Google. Many bloggers say that the Pagerank drop will have no effect on the way in which they run their sites.

"Google slaps down a bunch of prominent people, lets the buzz take over and hopes that the warning shot would be taken seriously by the rest of the blogosphere," wrote Aaron Brazell, director of technology for blog network b5 media.