Disc One:
-Commentary with Chris and Jonah Nolan
-Trailers and TV spots
Disc Two:
-"The Dark Knight: The Journey Continues" The concept, design, and developement of the film.
-"Back in Black" A look at the design and production new batsuit.
-"New Set of Wheels" The design and construction of the Batpod
-"Makes You Stranger" A day in the life of Heath Ledger on set, from applying the makeup in the morning to wrapping at night.
-"Genesis of the Joker" A documentary of the history of the Joker in comics, film, and television.
-"Joker Begins" How the character was reimagined for TDK, including concept art and costume design.
-"Gotham: Creating a World" Designing and building the sets of Gotham, and filming in Chicago.
-"Batman Has No Limits" The stunts and SFX of TDK.
-"Viral Marketing" A look at 42 Entertainment's viral marketing campaign.
-"A Tribute to Heath Ledger" A documentary on the life of Ledger, with recollections from the cast.
-Deleted scenes
-Outtakes
For the inevitable deluxe-whatever-limited-edition, I'd like to see goodies like
-Mini posters
-A packet of Joker cards replicas from those used in the film
-The comic adaptation of TDK
For the super-duper-
mega-expensive-limited-edition, I'd like all that plus:
-A special edition reprint of Batman #1
-A full-size replica of the Joker's Grumpy Mask from the prologue