The ins and outs of queues
Looking at the following diagram, we can see where Queue Storage fits in with the rest of Windows Azure:
As one of the three simple storage options, Queue Storage is created when a storage service is added to an account. The Queue Storage endpoint is listed with the others when we view a storage service, as shown here:
A single Azure account can have any number of queues. Each queue is composed of messages, each of which carries the data or processing instructions that need to be acted upon by the back-end servers (refer to the next diagram).
There is no enforced limit to the number of messages in a queue, although there is a practical limit to the number of messages we'd want stacked up at any given time. Messages with a long latency in the queue are an indication that either the back-end processes need to be further optimized, or we need to scale out some additional back-end servers.
Each message is simply an XML document, in Atom format; messages are limited...