This evening I'm listening to a presentation by John Graham "From the ESB to REST and Clouds an Open Source", who is talking about ESB, REST and Clouds at the SUN campus in Burlington, MA. It is a nice overview of the evolution of system architectures, with the conclusion that as system became more distributed we developed different integration solutions; from Corba, Asynch Messaging to ESB. The talk is spiced up by some good word plays ("Being thrown under the ESB"), quizzes and code examples. It's entertaining.
After a little while we arrive at Guerrilla SOA coined by Jim Webber, which is a lighter style of SOA. Finally we arrive at how REST can be used in a cloud environment in a complementary fashion to manage ESBs.