I just installed a firefox google pagerank extension.
I don’t know too much about PageRank besides the basics (you get ranked higher as you have more links pointing to you and as you are more “honest” about content e.g. your page content isn’t a bunch of random words).
However if I were google I think I’d model pagerank after the Richter scale (for earthquakes), where each additional increment is an order of magnitude increase, aka make pagerank logarithmic.