Another thing that might be useful (and I'm not sure if it was already included on the previous DVD release) is the original treatment Romero did for the film, which was something like 4 hours worth of scenes in a 300+ page script. It's readily available on the net (like here for example) and would be useful for completists who want to know everything about Romero's original vision.
I found a couple of text interviews with Scott Reiniger and Romero here (it's under the "Interviews" section). The webmaster of that site also seems to know about the beginning narration of the Japanese version (the cut that freezes out violent parts), so I will e-mail him asking whether he can send me a copy of the cut or if he can provide me with the beginning narration. Since this cut wasn't even screened in the U.S. (at least, I don't believe so), it would be a seriously collectible item, and whatever info I can dig up on it, it would be of interest to fans.
I will compile everything I can find for a DVD_ROM section.