Nope it's not. People running after PR because: 1) Normally your EPC (earning per click) for AdSense is higher than without PR 2) If you're competing with other page that has backlinks with other higher PR pages, that page will rank higher than you in Google SERP. 3) Credibility. Since lots of people is building theirs, by having one is like a privilege, especially in the eye of your potential customer. Cheers, Azlan (AzlanHussain.com)
PR is only one component of ranking high If you have low pr and still rank highly, its because you have other factors propping you up (onpage seo, niche topic etc..)
This is always funny to me. Of course a low PR can outrank a higher one, since PR isn't the only factor. If it was the only factor, then PR10 sites would rank first for EVERYTHING. For example, search for "The police tell everyone how to scam Del Taco". It's a PR0 page and it outranks Google's PR10 page, Yahoo's PR9 page, etc, etc. That being said, PR is still important. The number itself doesn't matter, but the links that go into certainly make a difference. Don't worry about the green bar -- just build backlinks.
Worth worrying? No. But PR is a result of good backlinks, and those are something to pay considerable attention to.
alot of high pr directories get pretty much no traffic at all what is meant by PR is usually google toolbar PR which only counts your links and isnt the same as actual pr which only google knows what really matters is relevency+links+trust etc etc..