In a recent ZapThink article, which has an amazingly similar name as my blog.... ;-)
I found this:
Ok. Pretty close... but I just want to clarify a bit.
First generation orchestrations are typically used as a process-integration or a system-to-system integration mechanism. This means that the orchestrations are VERY message oriented and the granularity between the operations are almost always coarse-grained.
In addition, there is a logical difference between "service orchestration" and "process orchestration". Typically, service integration is lower level. It involves the many calls to "technical services" and attempts to hide higher layer calls from the ugly technical details and are often exposed as a single business service. "Process orchestrations" are orchestrations that occur at a higher level. In these cases, virtually all of the calls are to other 'processes' and tie together a digital business process.
Now - in the future (2005+), I expect to see more fine-grained web services being used in 'composition' tools (a close cousin to orchestration). In this setting, more emphasis will be placed on in-lined services and performant service compositions. But for now, this is outside of the scope of what we typically classify as 'orchestration' or 'choreography'.