Back in December (2011), Microsoft released the Azure Service Bus EAI & EDI Labs. This is a sort of CTP with labs.
It’s built on top of AppFabric Service Bus, but seems to contain much more than raw messaging.
According to the MSDN documentation, it seems that a lot of BizTalk concepts were re-used. For instance, look at a ‘transform project’:
If you see a familiarity with the Mapping tool of BizTalk, you’re not alone!
I haven’t have time to really look at this new piece of technology. I just hope it won’t have the same curse than BizTalk, for instance making a simple scenario extremely complicated and being a deployment & monitoring hassle.