ESB is either the "real" kind or the "Monty Python" kind. Systems integration is the last true "black art" there is, and SI specialists make top dollar (I know!). There are plenty of ways to integrate software today - the real difficulty is enticing or forcing everyone to pick one. Just as it seems that "mature" software is becomming easier to integrate, some new startup, with cheaper prices comes along and upper management dumps it in your lap - setting your SI efforts back. I can't tell you how many times I personally worked with software vendors to make their offerings more "Company F friendly".
SOA is just the latest example of making interfaces between software more useful. I remember AREXX for my Amiga allowed disparate programs to interface with each other, as entry points (i.e. APIs) were accessable via AREXX (I believe mainframers would testify to the original REXX). The Amiga was WAY ahead of its time, too bad it was controlled by another "evil empire" - well Commodore was hardly an empire (largest installed base of computers in Europe in the 80's - more than PCs), and hardly evil - more like stumblebum incompetents than evil, however I digress!
As my many years of experience has taught me, I believe that we will see a company like IBM make AL of their applications ESB compliant - but use strange APIs and run ONLY on their hardware, thus limiting the usefulness of ESB and SOA. Internal API between programs will NOT establish SOA as the be-all-end-all, but EXTERNAL APIs (like google maps) will.
Enterprise service bus (ESB) is one of those hot industry trends that is promoted as a cure all for integration ills. Brenda Michelson, of the Patricia Seybold Group, just published a free article, "Enterprise Service Bus Evaluation Framework: Criteria for Selecting an Enterprise Service Bus as an Integration Backbone," that sheds ample light on the topic. It will clear up most of the confusion about ESBs, backbones, event-driven, SOA and other assorted concepts related to integration that IT executives often hear about, but sometimes don’t get the whole picture. Thanks to Jon Udell for the pointer.
