I disagree. The last version only had a message bus. Its an inversion of communication - instead of the Gateway knowing that it has to communicate to the other services, it just publishes an event and the inventory service knows that it has to listen to events from the Gateway (or even simpler: Just listen to 'inventory-updated' message).
Why is that different from an ESB?
IMHO ESBs have logic, transform events etc.
It doesn't have to. Could just be a series of queueing.
I agree. To me he just didn't talked anything about his topic. Althouth everything in this article does make sense, but what about the REST?