...mitigates some of the risk of operational upgrades, but ensuring your operational system is ready to continue delivering a liveservice once testing is complete is paramount. Companies of every size and across all sectors must research the most suitable...
http://www.computerweekly.com/Articles/2004/06/22/203235/Your-Shout.htm
...message over Microsoft® Message Queuing (MSMQ). Instead of sending the Windows Communication Foundation message to a liveservice, the client posts the message to an MSMQ queue. All the client sees and interacts with is the queue, not a service...
http://msdn.microsoft.com/magazine/21261a10-c387-4b4d-8705-284fcdc1ffe4