What really is "Business Process Management?" According to Darcy Fowkes of the Aberdeen Group, "Business Process Management defines, enables, and manages the exchange of enterprise information through the semantics of a business process view that involves employees, customers, partners, applications and databases. It has to be capable of modeling a process, brokering that process, delivering it with straight through processing (STP), and then managing it, all within a single environment. Because of its far reaching implications for the ability of enterprises to adapt, it is much more than a technology fad but a management issue that needs to be on senior management's agenda, driving the IT support of the business." link
I think this is a nice operational definition of BPM, from the business manager's perspective. I will just add analysis, simulation and optimization capabilities under the umbrella of BPM.
Given this broad definition of BPM, from the IT perspective, it encompasses many aspects including workflow, EAI, B2B, and extended value chain involving multiple partners. It is no wonder that every vendor is a BPM vendor and every system is a BPM system. Tibco, WebMethods, Savvion, Oracle, IBM, BEA, Microsoft, and many niche players are positioning themselves to be BPM vendors. Some offer EAI solutions, some are purely workflow, some are generic web service orchestration solutions, and some are B2B specialists. So, which is the real BPM system? The answer is both everyone and none. In reality, BPM system is not a single system, but rather the entire IT environment composed of multitude of systems doing multitude of things.
There is no problem with the broad and ambiguous definition of what BPMS is, except when it comes to defining BPM standards. Consider BPML and BPEL4WS which are touted as the next generation business process modeling languages that will form the basis for new generation of BPMSs. Are they really the next cure for cancer?
There is much more to a BPMS than BPML or BPEL. BPEL is primarily a control flow language (which is rich enough to model most workflow patterns), and supports message flow and limited (and sometimes ackward) data flow. It is not a complete language to support any of workflow, EAI and B2B processes (read the presentation of BPEL
by Paul Brown of FiveSight Technologies for a concise characterization of BPEL).
With all that said, the "new generation BPM systems" are aligned well with the technology trends (web services, SOA, XML, and probably even the future Semantic Web - how long before we hear BPEL process ontologies buzz?), and hence will definitely subsume the current systems (which are primarily workflow and EAI systems). The question is when and in what form will they be.