One of my sites was dropped PR by google from three to nothing since last year, due to this is one of my favorite domains, I don't want to let it expired, How do you think if I park the domain for half or one year, And then relaunch the site, Would the PR come back? Or do you have any good suggestion?
Some my sites dropped PR as well. Could work if we get quality backlinks more. However I don't care really.
Do not let it to expire. Work hard for that check for any penalty. Get quality backlinks and put some fresh content there. submit sites in high page rank and relevant directories and you will see the change. but will take time
Check what made Google drop you and rectify the mistake. then file a re inclusion request through the webmaster tools. The most common reasons for Google catching you are duplicate contents, scraper sites, link selling/buying, rigorous SEO etc.
i would not say PR is nothing, BUT the site is a web directory so some clients maybe care about the PR.
i would have to agree with seoonly def fresh material everyday will get you ranked higher then anything else
btw, you can also contact Google Management asking this problem. Some of my friends are getting their PR back after contact Google.