The PageRanks displayed on the toolbar are a score out of ten, and only a rough guide to the true PageRanks which Google keeps secret. It is only updated once every few months, so each update causes a stir which people interested in Search Engine Optimisation.
Around April 2nd, 2010, Google made its latest update, causing jeers and cheers from SEO experts as the website and pages they managed either dropped or increased in PageRank.
This was the first update this website was present for, and it was introduced with a page rank of 2. Many websites take years to reach this status, so I'm very happy.
Your PageRank is influenced by the number and rank of websites that link to your website. Check out my Link Building Check List to get started on boosting your PageRank.