I agree with that in general but having your monitoring system be dependent on the thing it monitors is a pretty big goof. It possible that the dependency was very non-obvious and many layers deep, which is more understandable, but still...its pretty fundamental.
They have a twitter account for such incidents and used it appropriately. They did not slack in relaying the outage to customers, and between that and the fact that no S3 services were operating I think the message was pretty clear: "We fucked up, give us a couple hours"
