For years, designing and developing applications inside of retail enterprises followed a fairly standard methodology.  I have represented this methodology in the image below.  To summarize:

• This methodology can best be dubbed "Corporate Centricity".
• LOB applications and corporate data stores represented the starting points for all application projects.
• The user experience (not purely the UI) was dependant on LOB application architectures and the limited array of services they provided.
• Each customer experience represented a physical and logical representation of the substructures extending out from the Corp LOB assets.  

Since the advent of the multi-channel context, retailers are coming to a view that designing a good, consistent user experience across channels is far more than a pretty picture, painted on a variety of devices.  True meaningful customer interaction is about form and function, with consistency at all points of interaction.  This view has caused retail architects to refocus their application design perspective, by building with the customer at the center of architectural design, as represented in the following image:

This conceptual approach takes a view that enterprise-class services must be available from all channels (including 'channel n'...the channel yet to be discovered/needed).  Architectures built from this perspective are more agile and more responsive to business constituencies like  marketing inside of retail organizations. 

While there is certainly a host of complexity beyond these very basic representations, a perspective whereby the customer drives application design is being leveraged as a competitive advantage inside of some very progressive retail IT organizations.