It is interesting that a relatively advanced piece of software, message queues, which most run of the mill projects most likely have no need for, has an interface that is compatible with a simple, straightforward protocol that was designed for everyone and their dog. I mean, if you need message queuing, you most likely have someone on staff who can design, write, and deploy a protocol language (especially if they can write the queuing software also) and who doesn't need to use compatibility libraries.

Great, your memcached-compatible queuing service can leverage all those memcached client libraries out there, but somehow I don't think that client libraries are the hard part of the queuing service.