My predictions:
Bethesda is going to stay away from doing anything related to fallout and instead talk about the doom
Ubisoft won't really do or say anything that anyone really cares about
Microsoft will forget the xbox: one exists and instead talk about pc gaming and the windows 10
Bohemia interactive will do arma III dlc stuff
Nintendo will have an all-around fun panel, but ultimately won't talk about anything that isn't already known
Sony will rock the house like usual
Nobody really gives a stuff about what EA has to say short of sports gamers.
Square Enix reps die onstage during a flood of bad hairstyles and shirt zippers
PC Gaming show panel will be cool, I don't have much on it