Forum Moderators: phranque
As for placing related websites on the same server with the same IP address, it is certainly a signal that the sites are related - but in most cases, other elements would already have indicated that they were part of a network (from whois data or toolbar data to the existence of heavy interlinking in the first place). It is impossible to say whether the IP change in itself will tip the balance and alter the way the link relationship is seen by Google or other search engines.
<edited for spelling>
[edited by: encyclo at 12:45 am (utc) on June 9, 2009]
I've seen many clients flip IPs and even to different subnets. I think the effectiveness of this on SERPs is limited these days. Whois records, content comparison and crosslinking provide much stronger indications that the sites are closely related.
Our site was consistently ranking between 8-11 for a nice keyword on Google.
Switched to a dedicated IP for SSL and other reasons. Since that time the site has dropped for that term to 41-50. That was over 2-3 weeks. Originally we dropped to around 14-16. And I just discovered the big drop recently.
Not sure if it's DC changes or what yet. Since Google is still driving traffic on other keywords.
Lucky for us other traffic is picking up the slack overall, we'll still be down a minor bit for this month at a minimum.