I thought it did better than The Dark Knight in exploring the theme of a hero's duty and responsibility, and it did much much better than Lost in integrating overlapping flashbacks to drive the backstory.
On the Shockwave Radio Theater scale of 9 to 23, I'd give The Watchmen about a 20. I may flix the DVD for deleted scenes. 2 hours and 43 minutes goes by fast.
There is no extra material after the credits.