Ok boys and girls. I believe I have finally fixed gravatar serving for real this time. I did some digging into the open_basedir problem and discovered that my host is now serving gravatar.com from two different internal servers, each one with a different location for the document root (and presumably different copies of all the files!!!). Strange, I know. Still trying to get ahold if this guy to straighten things out. So what this means to you, the end user, is that gravatars are now being properly served from both places, which I believe is what was causing the intermittent black/gray problem (one server could find the files, one could not). However, it also means I can’t enable logins yet, because of the dual file system issue. Patience everyone, patience. All will be healed in time. And thank you once again to everyone who has been supportive!
On a side note, is there anyone out there who is experienced with FreeBSD server administration and willing to donate their expertise to the gravatar project? I’m hoping to find someone to help me out with setting up and maintaining server(s) for G2. Go on, spread the word!