The human aspects of SOA are important for two reasons. Firstly because we want to talk about business services as well as web services. Secondly because we want to talk about agility (which may require human intervention) as well as efficiency (which might possibly lead to maximum automation).
To my mind, one of the opportunities of the service-based business is the vast potential for interoperability between human activity and software services. We can construct complex workflows across multiple organizations, we can connect knowledge workers and business intelligence tools across hyperspace, we can construct effective closed-loop management over extended business processes.
For example, IONA has recently collaborated on a product known as an Electronic Flight Bag, for sale to commercial airlines. This uses web service technology to produce a new kind of artifact, integrating some very complex information from a wide collection of sources. It delivers benefits to the airline by supporting the airline pilot in performing a range of navigation, safety and administrative tasks. The installation of this product into a commercial airline is both value-enhancing and structure-preserving. I believe there are aspects of this product that would not have been feasible in a pre-SOA world.
In many instances, complex services are designed not to eliminate human intervention, but to make human intervention more productive, more reliable, more effective - and possibly even in ways that are less frustrating for a human worker.
See previous post: SOA Human Aspects 1
[Update] Technorati Tags: SOA service-oriented interoperability Iona