One of the drawbacks of EC2 is that there are no static IPs to be had, so short of using an external (to ec2) solution, the only way to have redundant load balancers is to use dns round robin. If a load balancer instance goes down, we should ideally remove it from the round robin so that clients don't continue to use the dead IP.
Nettica is one of the few dns providers that has an API that allows changes to round robin records. They have a reference implementation in Java, but since I'm a ruby fanboy these days, I figured it would be nice to have a ruby version instead, so I added one to rubyforge: nettica ruby client. I did it as a gem, so assuming I released it correctly, you should be able to do a "sudo gem install nettica" and then run the simple test script "nettica -u my_user -p my_secret -c list_zones". This script still needs to be expanded to exercise the full api.
One thing that blocked me for the longest time was that the nettcia API required the password to be sent in Base64 encoding, which I was doing, but for some reason the ruby Base64.encode64() method was adding a newline to the end of the encoded string. Once I stripped that out, it all seems to work fine.