This was very amazing.How important is backlink with your PR?I will give you an example what good backlink can give you.Adobe have a more than 4 million backlinks and 30+ of their page are all PR 10.This are the benefits of backlinks in SEO.

here are some examples of the sites with PR 10.Go check them out.

http://www.adobe.com/government/main.html
http://www.adobe.com/web/main.html
http://www.adobe.com/enterprise/main.html
http://www.adobe.com/print/main.html