Should be starting 10PM PT and 1AM ET. There's about a 7 hour difference between Japan and PT so it's starting at 3PM in Japan.
There's a definete possibillity though that therewon't be a stream until 5ET via tape delay...there is a guy on Justin.tv though that strictly stream Japan MMA so hopefully a stream will be up on the dot.
Update Dream Fighters writes this...Start Time:
EST - December 31st at 5:00AM
PST - December 31st at 2:00AMlink