Late night PageRank Theories

I was just thinking back to when Google became a domain registrar. They said it was to learn how things work, but there has been speculation on how they use that data with regards to their PageRank technology. A few domains I had that I let go unregistered have a PageRank of 0, when they used to at least be a 1. Now some of these domains go to domain holding pages, but others don’t resolve. This would lead one to believe that they know when a domain expires, and they reduce the PageRank accordingly.

None of that is a new theory, but what I propose is that Google plans to use their access to domain registration data in order to know when people own multiple domains which they then use to try to increase their PageRank. I have tried this, and I have been unable to increase any of my PageRanks by cross-linking or any other methods. If they had access to registration data, they could compile connections between domain registrators. Say I register a few domains with the same user information, they would then be able to block any efforts to game the system for the benefit of those new sites or other sites.

Just an idea.