I am currently transferring some domain names from an old hosting package to my new registrar, it takes 6 days. Is there any risk of losing pagerank or google index in those few days? Considering the sites are crawled multiple times a day?
We had about 20 domains with basic pages then transferred them to parked.com. They kept getting search traffic for about 30 days then dropped off completely. It really depends upon where Google is at with updating and cycling through databases.
I'd say it depends if it's still used and how much traffic and backlinks it still gets by the next update? I'm not sure, just my idea.
pagerank will only change if the backlinks the domain has changes drastically, otherwise changing host or registrar has no effects on pagerank
If the websites in questions remains up during the domain name registrar transfers, it would have no effect on page rank or anything. It will only affect it if you drastic change the content of the site or remove it completely from the net for an extended period of time..