In the past, the audience is game studio heads and their producers to get the ideas flowing on what the novel capabilities of the new system are and how they can design games for it. Maybe some top engineering folks. Also for nintendo to get feedback from studios - "ah, yes, we've been thinking of doing augmented reality and it would be really cool if the camera had X feature so we can do Y in our game". AAA for sure, likely most indie shops. In the past direct competitors would not be invited.