I see that last year’s Dagstuhl workshop report has been published, titled “Executive Summary and Manifesto — Event Processing”. This is an excellent 60-page group effort by some of the great-and-the-good in event processing, and recommended reading!
The top-level Table Of Contents is:
Chapter 1: Why event processing?
Chapter 2: What are the characteristics of event processing?
Chapter 3: Synergies and relations to other areas
Chapter 4: Event processing related standards
Chapter 5: Grand challenge: The global event processing fabric and its applications
Chapter 6: Near-term research
Disclaimer/disclosure: TIBCO was a co-author of Chapter 4.