A good page rank is going to be determined by some good links to your site. If you can get any site with a higher page rank than yours to link to you without a reciprocal link, that is great. The more, the better.
Other than that, submit your site or blog to as many directories with high page ranks as you can. Sometimes it only takes a couple excellent links to your site to get you a really nice page rank. Getting a 3-4 is pretty easy. Getting higher than that, is very good.
You can check their PR's at
http://pr.blogflux.com/