Comcast will have New Moon On Demand and a directors commentary version which you can check out a clip below:

Comcast will have The Twilight Saga: New Moon On Demand beginning at 12:01 a.m. on Saturday, March 20 – the same day as the DVD release but HOURS before most retailers are even open.

AND, only Comcast customers will be able to view never-before-seen commentary from director Chris Weitz on a number of favorite ‘New Moon’ scenes such as: Bella’s birthday party, Bella’s cliff dive, when Bella rescues Edward in Italy and when Bella first meets the Volturi.

Thanks to Comcast for the info!