No, but... I still feel the need for an answer as to what caused it.
I have other alternatives for the software I'm developing, and those alternatives are free. Yahoo's results tend to be more precise, but if the service I use stops working, my software doesn't work and that's unacceptable.
I need some assurance of reliability so I know it won't occur again, or I need to switch. To give me such assurance, you'll need to identify the cause. Respectfully, "We don't know what happened but it seems fine now" isn't enough.
I've only used it for a week or so... that's not a good record. And this occurred after only about 5 successful queries.