Because one of the core stated objectives of Service Oriented Architecture (SOA) is to increase business and IT alignment and IT's flexibility in meeting changing business needs, on the surface it would seem that SOA and agile methods are a natural fit.  And within the SOA model of service production, distribution and consumption, use of agile development methods clearly has great opportunity for effectiveness on the consumption side of the equation. However, the approach by which a suite of generally reusable services within an SOA are defined and produced requires a cross-project perspective that could be viewed as running counter to a typical agile development approach. Some amount of up-front architectural thought must go into initial service definition to prevent those services being developed from becoming solely project-centric.  

In this article, the authors the use of basic patterns that can help build a software configuration management process that works well with your agile development environment. They discuss how codeline policy, private work spaces, smoke tests, private system builds, integration building, unit testing, and regression testing all work together to enable you to maintain an active development line.

Ramnivas Laddad talks about Aspect Oriented Programming, which isn't just for security and logging anymore.

When landing an airplane, the approach is considered quite important. If the approach vector is off even by 1%, the plane may careen off the other end of the runway. Also, if the approach is incorrect, effort such as fuel and time is unnecessarily expended and wasted, especially if circling must occur.