Collider.com did an interview with Catherine Hardwicke and they discuss the DVD already.
Collider: I'm curious, I know you just got back recently and I'm sure you're not thinking about yet, but what can we look forward to on the DVD/Blu-ray?
Catherine: Actually, I have been working on the DVD already. So we put together all the deleted scenes and extended scenes, there's quite a few, like 12 or something like that. And then I made some montages of some other crazy elements, like more vampire kiss, biting. And more human hijinks. And I made a pretty wild music video, like a remix of Bella's Lullaby and I did some pretty trippy things that you may like.
Here is the rest of the interview: