While watching session 408, about Protocol oriented programming, I kept asking myself why Dave appeared to leave the impression that POP is something different from OOP. Today I read a nice article about it, by Marcel Weiher, here.
... the idea was really to first get him all excited about not needing OOP, and then turn around and show him that all the things I had just shown him in fact were OOP. And still are, as a matter of fact. Always have been.
... The simple fact is that actual Object Oriented Programming is Protocol Oriented Programming, where Protocol means a set of messages that an object understands.
I think it's really worth the read.