First answer: People who play the aged website acquistion game do so very cautiously, doing their best to exploit the website's existing search engine status/rank. So some may insist that the WhoIs record remain constant for awhile or change something limited, such as the email address that controls the domain (if it's an ISP email, for example, to a domain based email). YMMV.
Second answer:
To the best of my knowledge, absent other factors, de-ranking a website merely because the WhoIs record changes would be nonsensical. IF it's the content and authority that matters then why on earth "weight" the WhoIs?
It may be 1 in 100 factors but, if I were designing an algo, it would be a very slight consideration, perhaps of some small consequence to newborn sites but of no moment to older, more established sites of some authority.
You've got to decide who's going to lead in this dance. My approach is to focus on what's going to work from the perspective of a) visitors and b) my business operations. As concerns search engines, I try not to accidently step on any trip wires - by being aware of stupid/dangerous SEO practices - and I study to maintain a basic awareness of accessible design and basic "search engine friendliness" (treat 'em like they're only so intelligent) but beyond that I go by rules that work for me.
If you sign up for the SEO game the rules keep changing. That's great for the SEO business but maybe not for your business. Focus on accessibility and user experience and, in time, the search engines will catch up with you . . or die due to their inability to deliver relevant results.
Thus ends the day's lesson in philosophy.
[edited by: Webwork at 2:28 pm (utc) on June 23, 2007]
