Gomvents - 2:59 pm on Dec 9, 2008 (gmt 0)
Google only looks for change in registrar data when it matches a drastic onsite change. As I've site before if you buy a site from someone you should wait about three months before changing the content drastically if you change the registrar data right away (as you should). Also the "content" shouldn't really change. If the topic changes of course Google should devalue old rankings as it's no longer relevant.