A little off topic: If you over-do it then NSNotifications easily can become distributed goto. Once I had to add features to a Mac application that made heavy

A little off topic: If you over-do it then NSNotifications easily can become distributed goto. Once I had to add features to a Mac application that made heavy (ab)use of NSNotifications. Following code paths was a nightmare. I tend to prefer the delegate pattern because there the relationships between objects are clear. Even if it means more work (creating glue code) - your sanity is worth it.