There are several possible ways to do this, but all copies should come with some customization extras that can't be purchased in game:
Digital only - Grants access to online extras like making of, dev interviews, high resolution art, etc.
Digital with an artbook - The above with a physical, nice quality hard back art book
Legit Collector's Edition - Physical copies of the game discs, hard back art book, and little Atlas / Catapult / something statue to put on your desk
If you would be willing to purchase a Collector's Edition, please tell me why! I'd like the devs to see this and be able to predict if it is financially feasable for them to do it (are enough of us willing to throw money at them before release).
Edited by Tsen Shang, 04 February 2012 - 11:51 PM.