You will see your PR change around the next Google toolbar PR update. PR 1-3 is fairly easy to achieve with a few hundred back links. For PR higher than 3, your back links should probably be coming from a high authority site; directly off the page with a high PR (not the PR of the main domain).
No matter what people say about the relevancy or non-relevancy of PR's, I personally think it is a great motivating stat for any webmaster. And yeah, there are people who denounce PR just because it decreased for their site. On the next update, if their sites PR increases, these same people start worshiping it. Hypocrisy at its best!!!