Whats so great about the new MVC2 areas?

Could some one please explain the advantages and disadvantages of using the new MVC2 Areas feature?

I don't understand what is so great about them. If I am adding an admin area to my MVC application why not create a new Adm开发者_开发知识库in folder in the main Views and Controllers folder? What does creating an area really get me?

This is what Phil Haack says:

The scenario that areas address is being able to partition your application into discrete areas of functionality. It helps make managing a large application more manageable and allows for creating distinct applets that you can drop into an application.

An admin section wouldn't qualify as an applet as it logically belongs with your application and may even share models with it.