Seems like if you are serious about mitigating this type of issue (as a consumer), you really should be specifying name servers from different providers. Your primary DNS server can be from dnsimple/zerigo/dnsmadeeasy and your secondary can be route53, or you could run your own.

The only problem seems to be keeping them in sync. Seems like you'd have to poll the primary (using whatever API it exposes) to update the secondary.

Mostly thinking out loud, surely someone more experienced could provide better guidance?