Ilya Grigorik, Co-founder and CTO of (AideRSS / PostRank.com) gave a presentation on "Event-Driven Architectures" at meshU.
At its core, event-driven architecture is simply an implementation pattern that explicitly separates the roles of “event generators” and “consumers”, as opposed to building an application or service which is responsible for the entire cycle. A simple example might be an incoming request to generate an invoice for a new purchase. In an event-driven application, the service would record the request, notify the user that it is being processed, and then send out a message to a “consumer” process, which will then generate the actual invoice. By doing this, the user receives immediate feedback and the actual heavy processing is done in a standalone process. The end results is faster response times for the users, and easily scalable infrastructure for the developers.
Here are his presentation slides: