I like this article discussing Pagerank and achieving `authority site` status-
A goal of many webmasters is to have their website achieve the status of an authority site for their most important keywords. An authority, or sometimes referred to as an expert site, requires strong content, a large number of pages, and a large number of incoming and outgoing links that are themed to website content.
Itís widely considered by many observers that the Google algorithm places great importance on authority site status. It is a goal well worth striving for with your site.
An authority site also requires a healthy dose of PageRank. Most authority sites have at least a PR7, with many being much higher. It should be noted that the size, in terms of number of indexed pages and the content of a site, is also very important in recognizing authority sites. PageRank is only one of several authority site attributes, but is the one we are examining more closely right now.
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