Your page rank has absolutely no effect on your actual rankings. Google page rank is just a tool used to gauge and grant numbers ranging from 0(new website) - 10( established website).

However one should only concentrate on increasing actual SERP search engine rankings rather than being concerned with the Google page rank.

If you are in a web design industry, and your design is one of the most creative designs in the industry. then your customers wont give a damn whether your website has PR1 or PR4.

Try to concentrate on the actual rankings of your website rather than PR. The only benefit of having a good PR is that you can submit to various web directories and can manage to get a page 1 listing under the parent categories ( if directory has arranged links according to PR )