Good article! I always describe Cocoa's learning curve to new programmers or to experienced programmers coming to Cocoa from other languages as a "grokking curve". Cocoa has a different view of the world than .NET or Java. If you come to the table with some programming background, you can learn the syntax and messaging model and enough to get started programming in just a day or two, but you don't really form a gestalt until you've been working with it for a while. Then, it's like a little light bulb goes off over your head, and you become a raving Cocoa fan-boy. :)

Hmmm... I miss Cocoa... I need to find an excuse (and time) to get back into doing some Cocoa programming.