We haven't used it yet, but we have done some tests with tasks.
So we will setup a milestone with tasks and subtask like we need for every project. In our case we would have a introduction period, then move on to the pre-production, production and post-production, each with default tasks.
The templating system would make it easier to copy this complete structure each time for every new project. Just go to administration area and create a new template, give it a name and add your default milestone/task structure as the object to copy (The link is called "Add an object to this template"). Within the popup you select the task you created earlier.
