It looks like come September you won't have to wait for a day or two or three anymore for Domain Name Service changes on the big-two TLD's to propagate when you add a domain (and possibly when you make a DNS change - still trying to figure that one out) on the Internet. All I can say is - what's taken so darn long?

In an email notice, Matt Larson of Verisign says:

"VeriSign Naming and Directory Services (VNDS) currently generates new versions of the .com/.net zones files twice per day.  VNDS is scheduled to deploy on September 8, 2004 a new feature that will enable VNDS to update the .com/.net zones more frequently to reflect the registration activity of the .com/.net registrars in near real time.  After the rapid DNS update is implemented, the elapsed time from registrars' add or change operations to the visibility of those adds or changes in all 3 .com/.net authoritative name servers is expected to average less than five minutes."

What that means is fast propagation of .com and .net DNS registration information on the primary Internet domain servers. From the Verisign DNS Rapid Update FAQ page:

How long will it take from when I register a domain or make a change to an existing domain on my registrar's web site until I see the change in DNS?
It depends on how the registrar's systems work and how long it takes the registrar to communicate your request to the .com/.net registry. Once the registrar successfully submits a command to the .com/.net registry, the new domain or changes to an existing domain should be visible in DNS on average within five minutes.

Verisign, however, will not be changing the current default TTL on existing NS and A records from 48 hours due to requirements of the DNS spec, which is explained further here.
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(via Slashdot)