You're probably right, but technically it depends.
Are the nameservers changing? I use a separate company for all my DNS stuff, so, if I were to switch providers I wouldn't technically need to point my registrar to a different set of name servers.
Assuming they ARE changing, yes, you will need to:
- Update your registrar and tell them the names/IPs of the new name servers at your new host.
- Update your DNS entries to point the WWW and whatever else requests to the IP addresses of your new servers.
However, if they are changing it brings up a question: Won't you have to re-set up your MX records if the name servers are changing? Even if the MX records need to be the same values, won't they have to be set up at the new name servers?
-tom