Pagerank is not of much importance. I actually came to this conclusion after seeing a blog of PR0 (formerly some high PR) ranking 3 for a keyword that is searched almost 906 times a day(from wordtracker).
Go to google.com and search for: make money
the third result you get is: 5xmom.com
Go to the blog and see the PR. Yes, it is zero. But it had a good PR first and after Google's action on the blogs that sold text links, that blog got a PR0.
P.S: I don't have anything against that blog and in fact I read that blog once in a while. Just to prove my point, I showed that as an example.