An early prototype of the Ruby interface for Amazon's Route 53 is available on github and as the route53 gem. You can install the gem by typing the following.

gem install route53

There isn't any documentation and the command line interface isn't done yet but this should get folks started that want to create a zone or two along with some simple records.

https://github.com/pcorliss/ruby_route_53
https://rubygems.org/gems/route53

Edit: No longer a prototype http://blog.50projects.com/2010/12/amazon-route-53-interface-friday.html