Service oriented architecture is about much more than integration using web services technologies - it has the potential to enable IT and the business to start to talk and collaborate using a common language.
There are four steps involved in getting to this common language: using SOA to increase software flexibility, increasing software reuse, increasing the comprehensibility of IT to the business, and increasing the visibility of the value of IT.
The first two steps are the most talked-about aspects of SOA, and they are closely related. The first is basically about using SOA simply as a way to carve up existing applications, and develop new systems in a modular fashion, so that changes are potentially localised and the impact minimised. The second is about organising a portofolio of services so that as many of them as possible ca be shared across multiple systems.
