if you care, planned UF outage this weekend

A real admin would have a live replication copy of the site on the new server and have zero downtime.....and you wonder why you can't get a job sitting around eating berries and watching King of the Hill.
 
Set the TTL in your dns zone file to something low, like 500 seconds. Thus the changes would be propegated more quickly across the internet. Then once the new server is up and running, put the TTL back to a normal setting so as not to flood your server with unnecessary dns traffic.
 
Set the TTL in your dns zone file to something low, like 500 seconds. Thus the changes would be propegated more quickly across the internet. Then once the new server is up and running, put the TTL back to a normal setting so as not to flood your server with unnecessary dns traffic.

(my dns-fu is VERY weak)

the DNS servers will be changing as well, so will that still matter?