Just received another announcement from the Windows Azure Team:
On October 27th, we will update the Service Bus to include relay load balancing functionality with support for up to 25 listeners per endpoint. This service update simplifies the task of building continuous, scale-out services and hybrid applications that take advantage of existing backend systems, applications, and services, across trust boundaries.
This update does not involve any changes to the SDK. The primary impact of this change on your code is that opening additional listeners (more than one) on an endpoint will no longer result in an error.
Please note that this new feature can potentially change the behavior of existing applications. If your application relies on the service behavior of allowing just one listener on an endpoint, you need to ensure your code limits the number of listeners per endpoint to one. Not doing so might also result in receiving charges for more connections than intended.
If you would like to take advantage of the new relay load balancing feature, your code should be updated to manage the number of concurrent listeners per endpoint and provide limits to your desired number of listeners per endpoint.
Additional information on this new functionality will be available on the Connectivity and Messaging forum and Service Bus release notes site beginning October 27th. Should you have any questions on this release, please visit Windows Azure Customer Support.