Finally, the ultimate definition of Google Pagerank, at least for the next 3 weeks or so.  If you really want to know, it is all right here:

PR(A) = (1-d) + d(PR(t1)/C(t1) + … + PR(tn)/C(tn))

that's it, that is the formula for Google's Pagerank…now go here to read the full explanation

Here are some interesting notes.

Frequent content updates don’t improve Page Rank automatically.
I really don't think this is true… I've done a few experiments with Wordpress blogs set up with auto-posters that post articles from article databases. These sites had no links coming in, and the page rank was solely based on fresh content. In about 3 months they reached PR3.

Efficient internal onsite linking has an impact on PageRank.
This might explain the above link, since the "experimental sites" had many internal links based on sub domains.

Site can be banned if it links to banned sites.
This seems scary to me, since you probably don't know what sites are banned.

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