i use
hostnine reseller plan .. there i have the option to select the location of the server (multiple datacenters - multiple C classes). they also have the option to use my own DNS for each domain (for ex: ns1.mydomain.com , ns2.mydomain.com .. ns1.myotherdomain.com , ns2.myotherdomain.com).
my question is: this DNS is basically a clustered IP, so my DNS ns1.my-domain.com have the same IP with ns1.my-other-domain.com. Is this make a difference for big G00gle???