I don't see how you can call this a subtle pattern distinction.
MVC contains 3 words: 'model', 'view' and 'controller'. These interact completely different in "real" MVC and in most "MVC" web frameworks.
The point isn't the observer pattern; that's just a tool. The point is that in MVC, only the controller talks to the model. The model in turn notifies the view, but doesn't know anything about it. In Rails & co, the controller knows a lot about the view. Also, there typically is only one view per controller. These limitations are not there in real MVC, because the controller does not know anything about the view.
This nearly complete independence of the three components of MVC is what makes it good. Exactly this is what traditional web frameworks don't have.
MVC contains 3 words: 'model', 'view' and 'controller'. These interact completely different in "real" MVC and in most "MVC" web frameworks.
The point isn't the observer pattern; that's just a tool. The point is that in MVC, only the controller talks to the model. The model in turn notifies the view, but doesn't know anything about it. In Rails & co, the controller knows a lot about the view. Also, there typically is only one view per controller. These limitations are not there in real MVC, because the controller does not know anything about the view.
This nearly complete independence of the three components of MVC is what makes it good. Exactly this is what traditional web frameworks don't have.