sem4u - 9:37 am on Nov 1, 2011 (gmt 0)
I would love to know how PPC (directly) increases PR. Also, traffic does not affect the PR of the website - only links can do this.
Today PageRank is a bit of an outdated concept. The toolbar value is not updated regularly. You are better off looking at the quality of each website that you would like a link on. The Moz rank of a website or page is also something else that you can check, which many people think is a more reliable rating than Google PR.