Are you guys just making this stuff up, guessing, or intentionally trying to mislead people? There are people here with hundreds of posts spouting absolute rubbish! Page Rank is critically important in determining where a particular page appears within the SERP's. Page Rank is the algorithm used to determine the importance of each document within a set. In the widest possible sense, that means the entire World Wide Web. It's a lot more than a number you get from a toolbar. Read the patent. Or at the very least, read the Wikipedia entry (sorry academics!)
I think it is not so! Keyword density and high quality incoming links from topic related sites are the most important factors for Google! Page Rank plays less importnat role for website rankings in Google today!
Pagerank has some value but quality backlinks should be of the main concern. A backlink from a niche site with a PR2 is way better than an untargetted PR7 link.