You bought the domain.
The content that was on it before you bought the domain was PR2.
Now you changed the content and Google doesn't like it.
Your content isn't as valuable in Google's eyes.
You might as well have bought a new domain for what it's worth, the only thing your domain might have on it's side is age.
Sorry...
Disagree.
He just bought a domain with Fake PR. There are thousands of expiring domains with fake pagerank. I could only guess why.
PR dropped to 0 and all the previous links are unrecognized.