Okay, I think I've found the cause, and it's not anything we have control over.
Level 3 Communications, one of the Internet's largest backbone carriers, had a fiber optic trunk cut a few weeks ago. It's caused major Internet congestion and massive slowdowns all over the Web, particularly in and around Texas--where our hosting company is headquartered.
Level 3 is working to repair the trunk and reroute around the problem, but it's been causing headaches all over the Net for weeks now.
