I think my host decided to upgrade the server TMINE runs on yesterday, because as well as an hour or two downtime yesterday morning, they did something to PHP that killed off the Disqus commenting plug-in. As a result, you may have found pages unable to load beyond a certain point. I've now recoded the pages to access Disqus differently, so fingers crossed the problem will go away and you'll be able to comment again
So a big hearty congratulations to Livingdot for their usual customer service and apologies to everyone for the interruption in service. Also, a big thank you to Fred, who emailed me to point out the problem! THANKS FRED!