Mediation or Intermediation?

At the InfoWorld SOA Executive Forum yesterday I was on a panel with Annrai O’Toole, Graham Glass, Frank Martinez, and Gordon Van Huizen. The topic was the SOA Platform – what is it?
The summary I heard over lunch is that there’s very little agreement on terminology, but everyone at least agrees mediation is required. Paul Krill also posted his impressions on his blog.
This relates to the recent debate about ESBs. A big topic of debate, as Paul notes in his blog, was the ESB term.
In this trail of blog entries and comments, I find it a great that Microsoft is talking about standards. I can remember a time about 10 years ago when that was not the case.
However I find it hard to believe that Microsoft, IBM, Oracle, BEA, SAP etc. are going to implement exactly the same set of standards in exactly the same way. IBM and Microsoft currently promote different versions of the “Web services stack.” For example, IBM supports Grid computing and all the specifications associated with the Web Services Resource Framework (WSRF), but Microsoft doesn’t. Microsoft supports WS-Management, IBM doesn’t. IBM supports the Liberty Alliance, Microsoft doesn’t.
Not even WS-I compliance ensures interoperability, although of course it helps. As long as the world of computing is complex, multi-platform, and heterogenous we will need something like the ESB to mediate between disparate environments, and make software work together.
I am looking forward to the next round, May 17 in New York. The issue of what constitutes the runtime for SOA based on Web services is a critical question of the day, and deserves this kind of debate.