Hm, it just occured to me that a very small fraction of the web is still likely not resolving my domain name correctly. I switched secondary DNS servers when I switched ISPs, but the old secondary still apparently is running with my old IP addresses. So, anyone who asks that server for the IP address of my site will be mislead. Web browsing obviously won't work, then. I'm a bit more curious about e-mail sent to my domain. Will it eventually be delivered correctly even if the sender's mail daemon initially has the wrong IP address? Is it bouncing back to the sender? Is it just silently disappearing? I've recieved no messages from the domain from my old secondary in the last week.
In any event, I've sent mail to the bind maintainer at the old secondary. With luck, this will all be moot in a day or three.