The question of how Google may use whois data in ranking or spam detection has been discussed over the years time and time again. There are many ways Google could use the data, from checking who owns which web sites, checking site age, checking transfer of ownership of domains, and possibly for some sort of keyword relevancy factor.
The keyword relevancy factor is now being discussed at a WebmasterWorld. One person said that when he Google'd his name, a site that he owned but had no mention of his name on and no links pointing to the site with his name as the anchor text, came up. Thus, he suspected Google used whois data, the registration data, to match the site with his name and show it as a keyword match in the search results.
I just Googled my own name and found an interesting result in position #3 organics was my 10 year old website. The interesting thing is that there is no reference to me at all anywhere on the site. The result was the index page and of course there was no highlighted text that matched my name search. It's a pretty strong indication of whois influencing search results I think. I wonder if they can and do use whois to track those who would flirt with the dark side...
Do you think Google would use whois data for keyword relevancy matching? Does it make sense to do it this way?
Forum discussion at WebmasterWorld.