Xd for process

When we think about eXperience Design, we often are thinking about an application and how a user interacts with it. How would it look if we take Xd methodogies and applied them at the process level?

One of the most successful examples that comes to mind is iPod - iTunes - iTunes Store. The experience is fully realized when you bring all three together. Each on its own has been executed well but would each be as successful without the others?