After much flailing about and gnashing of teeth, you should now be seeing this site served up by my new webhost. My original plan to use FastCGI + PHP CGI didn’t pan out (for some reason). But with other improvements to my configuration, I think that the new setup should work pretty well.
After it’s had some time to burn in, and I have the chance to twiddle some more knobs, I’ll try to post a few tidbits of what we changed. The real test will be after I make a WordPress-related post and see how it handles a surge of traffic.