Does SOA require an ESB?

For those of you not subscribing to InfoQ, I just want to point you to this article, dealing with one of the cornerstones of how we recommend our customers to design their ESB, with or without an SOA perspective: Don’t Let Consumers and Service Providers Communicate Directly. It ends with a conclusion that I see pop up over and over again (and one that I agree with): No, an ESB is not strictly required to build an SOA, but it can sure help.