I've found myself more and more talking to people about SOA because of my background with distributed computing. Over and over, in these discussions with CIO's, CTO's, and CCYAO's, they keep talking (without realizing it) about Customizable Rube Goldberg machines.
Rube Goldberg is a cartoonist whose name made it all the way to the dictionary:
Rube Golderg - n. A comically involved, complicated invention, laboriously contrived to perform a simple operation.
Rube Goldberg was a Pulitzer Prize winning cartoonist, sculptor, and author who lived from 1883 - 1970. He is well remembered for his cartoons (thus the dictionary entry), some of which everyone has seen (maybe without realizing it). Here is Rube Goldberg's "Simplified Pencil Sharpener":
Many SOA architectures look just like this diagram, with similar unintentionally ironic names. As I wrote before in Entropic Software, software tends towards complexity. It seems doubly so that enterprise architecture tends towards (frequently needless) complexity. Every SOA pursuit I've ever seen could stand some significant simplification. Of course, most consultants won't say that; they view monstrously complex software as job security. That is perhaps one of the differences from mercenary consultants who are only in it for the buck (complexity == $$$ + long periods of time == job security). If, on the other hand, you have someone who is trying to implement what you need, the tendency should be towards simpler architecture and systems. This isn't a slam against big consulting firms (I know some guys who work for the biggest who really care about what they do, and they would agree with my assertion).
The Snake Oil here comes from C(x?)O's who believe that Rube Goldberg-like complexity is inevitable, and this myth is perpetrated by mercenary consultants. Like Rube's "How to Tee a Golf Ball without Bending Over":
The key to successful distributed computing lies with extreme simplification. The most scalable distributed architecture in the universe (as far as we know) is based on a very simple protocol: HTTP. The key to successful SOA endeavors is two-fold: simplicity and testing.
You can read more about Rube Goldberg and see a whole gallery of his work at www.rube-goldberg.com.