So the iPad has hit the stores in the US. Being both London-based and by nature a late adopter, it remains but a concept to me - but how others who now have the much-hyped tablet in their hands react does catch my eye.

Chris Nuttall's observation in the Financial Times that 'the tablet is more about consuming than computing' offers an important insight into the wider development of the ways through which we now create business value from the capabilities of contemporary technology.

When I moved into IT in the early 1990s as Group CIO of ICI, I inherited a team whose prime focus was on making the technology work. The technology was still young, and the process of moving from the central mainframe 'temple' to the desktop was in its infancy. I inherited responsibility for several such temples, and the functional power lay in their management. The emergence of the server in the broom cupboard, and with it the distributed desktop, threatened that central control. The desktop gave new influence to the user, and the servers empowered the individual ICI businesses; the temples, nonetheless, remained a vital part of the whole.

My response was to outsource the temples and their allied network services. The immediate motivation was not just to save costs but to more effectively position ICI for an intensive few years of proactive acquisition and divestment. As I later briefed the ICI staff affected, they were much more secure for being employed by a focused and specialised third-party supplier of IT services operating safely away from the fray of an endlessly restructuring ICI. They were, de facto, primarily specialists in 'the computing', while what the ICI businesses really needed in-house was chemical industry-relevant expertise in 'the consuming'.

The concept of services was creeping into use. When the guardians of the datacentre temples moved to a more arm's-length relationship with their old client ICI businesses, it suddenly became much clearer that they were delivering services. As for the IT professionals, the 1990s marked the emergence of those with skills and experience focused on delivering 'the consuming'.

For the next decade, the competitive forcing ground for this evolutionary split lay not in the corporate enterprise but in the consumer markets. Consumers buy kit but they use the kit to consume services - and the services they consume became the real marketplace for the likes of Google, eBay and

Peter Rowell of Regent Partners International has noted 2009 as the year in which Symbian and RIM still held the high ground in smartphone unit shipments but Apple suddenly surged way ahead in content delivery. Behind that surge lay the phenomenon of the iPhone App and the iPhone App platform.

The App platform is 'the computing', a delivery vehicle underwritten by integrated data processing and network capabilities operating as service manufacturing facilities. iPhone Apps offer endlessly innovative user capabilities, 'the consuming' - and thus the Apple surge. This is a powerful illustration of the fundamental bifurcation of the professional role in IT.

The service manufacturing and delivery role focuses in the plant, along the service delivery logistics chain. It is where the battle to operate with high levels of flexibility and responsiveness, simultaneously high asset utilisation levels, and to deliver the green agenda and to ensure basic security, is won or lost. It is where innovation is inwardly focused on doing these things more efficiently. Above all, it is where service delivery has to be at the core of enterprise culture. It is the workplace for a very distinct breed of IT production professionals whose commercial value is now more widely recognised. This is 'the computing'.

In contrast, 'the consuming' draws on the work of a very different breed of IT professionals. This is the arena of how people work and how the networks and communities they constitute perform in practice. Little wonder that Apple leads the pack - it was the first to properly understand the human dimension, as opposed to the technical dimension, of the design imperative. The web and its graphics have drawn in a whole new breed of creatives. This is 'the consuming'.

And what is the message from all this for the contemporary CIO? It is that 'the computing' is now a very distinct professional and business reality. If you are a consumer of such services, delegate it to the supplier professionals. If you are a supplier, focus fully on ensuring your competitive effectiveness and efficiency as a services supplier.

The real competitive value-add for most firms lies in delivery of 'the consuming' to clients. Is that where the skills and experience of your in-house team is focused? Is this the core competency of the front-line suppliers you have chosen to partner with? Your business is more about 'the consuming' than 'the computing' and you should focus accordingly.

Richard Sykes was vice president of IT at ICI in the 1990s and is now a consultant