[Rails 3] How do I use the new hook functionality to hook up multiple generators for scaffolding etc.

I have ported a few Rails 2 generators in the past week and have learned a lot doing it, but I still don't understand how to take advantage of the new 'hook' functionality, which should make it easy to hook up multiple generators and have one generator calling multiple other generators. Anyone has any idea how this works from a generator perspective and how to extend and customize it. I know there are some trivial examples in the official Rails guide.

Do you simply have to specify the hooks in the application.rb in the config section and then add hooks in the generators matching these names?