Rob Daigneau's presentation on Introducing Domain Services was a pretty decently balanced between "astronaut-y" architecture and practical advice. He was a fairly engaging speaker. Probably the biggest takeaway I got from his talk was: "If you want to do anything useful in software, coupling must exist". He spent a good deal of time discussing this paradox - we want to have loosly coupled everything, but at the end of the day, if our code is going to do anything, it has to be coupled to other code in some way. So, in the end, its a matter of determining what type of coupling is best for a given scenario - different systems will have different needs.

He described the types of coupling as: