Our PR did go down a couple of months ago, but our Google traffic actually went up. I started researching the issue hardcore to figure out how that was possible, and gaystoryman is right. Google PR is becoming deprecated. It has almost nothing to do with rankings on keywords anymore. Even though our PR went from a 5 to a 4, our site is crawled every single day. Yesterday Google crawled 56,636 pages on the site which is about average. Also, it has crawled the site 90 out of the last 90 days which is as far as I can see back using their webmaster tools. As long as the traffic is up, I'm not too worried over PR especially after everything I've read on all the SEO boards the last couple of months.