I'm sorry but you are wrong about this. PR has nothing to do with the quality of your content (or lack thereof). PR has only to do with the BackLinks to your site. A site could be very spammy but if you manage to get a few PR4 or PR5 links to it, it would easily score PR3.
Thanks for all the reply here. After a week of monitoring my website in Google's SERP, My website is now back on their listing but dropped 2-4 on the serp ranking. It might be what they called Google Dance or something like that. What's weird is I'm checking it every hour sometime it'll appear and sometime it'll not. Then after 5 hours if you'll check it again it'll be back with different serp position, sometimes on the 1st page or in the 3rd page. This Google dance is insane!