Well, I've tried everything.
I've got two sites that are exact duplicates of each other, using WP version 3.3. The only difference is the location (one is on a dedicated server and one on a separate shared server).
See for yourself:
Any help would be greatly appreciated. I've stared at the problem so long I think I have tunnel vision! It's amazing that I have trouble-shooted problems infinitely more complicated than 'this box doesn't x out' yet this is the one that I am literally about to give up on.