SOA : The most understandable and profitable realization approach.
Rise of the concept of service oriented architectures became the obvious step on the way to the the solution of the most important and complex problem of the IT Industry - the problem of the application integration.
Virtually every enterprise runs nowadays on top of the distributed IT infrastructure, which is federating many heterogeneous platforms, applications, and legacy systems. The most of the modern enterprise have needs of the support of the links with the partners in terms of the corporate IT. Another important goal is the efficient reaction on the processes of integration, who that can be considered as the main priority for the IT Managers.
Those goals and circumstances are the base of the EAI approach of SOA realization. Personally I believe in this approach as most understandable and immediately profitable.