Another talk I saw at MVPMIX was Barry S. Stahl on loose coupling.

This talk was what you might think it was. His slide here shows off the Dependency Inversion Principal and the Single Responsibility Principal at the bookends of the SOLID stuff. The emphasis on the Single Responsibility Principal surprised me at first and then he clarified that he means "do not do the repository thing" (I'm paraphrasing) and that reading and writing should be broken up ah la CQRS and the like.

With the Façade Pattern one may create a false front overtop of an API, wrapping it.