I know there has been previous requests before, but nothing really became of it.
At the moment i used Route53 almost exclusively for my DNS, there are many advantages. Anyways, it could be great with some implementaiton for support with external DNS services, route53 (others are also available).. I know AWS R53 has a php library, and a cli too.
If there is nothing planned, i might look into writing one myself. Just dont need to be re-inventing the wheel here :)