The latest addition to the list of on demand message queuing service providers is CloudMQ. See my earlier coverage on the list of on demand message queue providers here. The article also answers the question: why enterprises may choose on demand message queuing integration mechanisms.
CloudMQ seems to have been built leveraging AMQP with Amazon EC2 and S3 components. CloudMQ overcomes some of the shortcomings in Amazon’s SQS such as JMS Support, message order preservation, and unlimited message sizes among others. While the SOA tag may not sound all that interesting for enterprises to adopt CloudMQ, however, the customer has more choice in this area from the providers such as Amazon SQS, OnlineMQ, Gnip and RabbitMQ (Erlang based and built over AMQP) and SaaS integrators such as CastIron, XAWare, Boomi, Jitterbit and Hubspan.
Other articles of possible interest:
Gnip, Online Message Oriented Middleware (MOM)
Value proposition of SaaS integration