In an event driven business, products are built to order, not built to stock, reducing inventory carrying costs and allowing greater customer satisfaction as a result of customization. This article from ebizQ has a great analogy:
If you want the train to move over one foot, you have to do an immense amount of work tearing up and re-laying tracks. On the other hand, all you need to do to turn the more agile truck is move the steering wheel.
Historically, we've been better at laying tracks in IT that we've been at designing roads. The Internet is probably a counter example. Its flexibility has been its greatest strength. The article, entitled "SOA It Goes: The Agile Enterprise Goes Mainstream," talks about the relationship between event driven businesses and event driven IT. With Web services, we're trying to recreate the flexibility of the Internet in every application. That's a tall order. Perhaps the best line in the article, for me, was this one:
[E]vent-driven, service-oriented architectures integrate three kinds of data: reference data, such as the number of trucks in a fleet; state data, such as the number of trucks under repair; and event data, such as a delivery being completed.
I'm not sure why it stood out, but, it seems to be a useful taxonomy. I'd be interested in hearing if others have used this or a similar taxonomy to classify data in an architecture and what benefits there were.
Reading the article, an another I found at the same site while I was researching SOA performance monitoring, led me to wonder about the tie in between the Iteration Real-Time reporting suite I reviewd a few weeks ago in InfoWorld and Web services. While not specifically sold as a Web services monitoring tool, it could easily be tailored to that end and would provide some interesting visualizations.