I read the following story about “post-it developlment” (or maybe I should abbreviate it to PiD to make people use it). In short, it’s a story about a software project where requirements are vague or floating but they’re still supposed to deliver. The one thing that got me about this story was the balance of the project manager, a former developer who had now turned manager. The agile manager must balance a sharp edge between leadership without being imposing. Apparently, this guy manages this. A great story from conchango.com.
http://blogs.conchango.com/howardvanrooijen/archive/2005/07/08/1780.aspx

As mentioned before, some managers might have a tendency to formalize the project, assign roles and responsibilities and building a hierarchal structure of the project, hence imposing a structure that the team might not be comfortable with.

The technical manager type might have an overall architecture and an imposing framework he wants everybody to work after, but might end up doing all the work by himself.

The agile manager has enough leadership for the team to be comfortable with the team organization and collaboration. He’s also making sure that assignments have a progress and impediments are removed. And at last knowledge enough to help coaching any team member that’s stuck with a technical challenge. The team is allowed to find their path to reach the goal but at the same time must honest and follow project rules like coding standards and practices like test first, refactoring and code reviews.