That’s because boards.straightdope.com still points to the old IP address, not the new one. Wait a day or so for the DNS info to propagate and it will once again resolve properly.
I remember years ago waiting for DNS propagation for two or three days before it resolved for everyone. I guess there have been improvements to the DNS server network since then.
I think so. I’ve always heard the “24-72 hours for propagation” thing, but everytime we’ve made changes to our DNS servers, we get clients all over the place hitting the new addresses within just a few hours.