In April 2009, I purchased about 6 expiring and auction domain names with google page rank ranging from PR3 to PR5 and on May 25 the Page Rank was Removed on ALL them and now have a page rank of 0.
 
I used Register Compass service to search for PR3 to PR5 domain names and their service verified that they all had valid page rank before I purchased them.  I also used http://checkpagerank.net/index.php and they also verified the domain names I purchased had valid page rank.
 
I heard all this buzz how Google loves Blogs so I joined MyarticleNetwork.com and used the articles from their network on sevreral of my newly purchased PR3 to PR5 domain names
 
My intentions of buying PR3 to PR5 domains was to build blogs and have links to some of my site to help increase their page rank and traffic.
 
There was a PR6 which I wanted to bid on - Pku100.org.   It ended up going for hundreds of dollars.   I offered to buy it and the owner wanted $5,000.  I checked on May 30, 2009 and all of the Domain Names I had connected to MyarticleNetwork.com's had a page rank of 0, then in a few weeks were completely removed from google's index.   Pku100.org's page rank went to 0, then in a few weeks went to PR4, but never returned to a PR6.

 

Man, I'm I glad I didn't pay hundreds or thousands for a domain which is now about worthless.
 
Seems that Google is really making it difficult in every way for people to make any money on the internet.