Sean McGrath has an interesting view of EAI. Basically he thinks is all about dispute resolution.
Computer system A sees the world one way, computer system B sees the world another way, computer system C has a third way and thinks A and B are deeply wrong in how they see the world. etc. etc. The custodians of systems A, B and C need to work together for the good of the greater organization.
That fits pretty well with my experience.