I dunno if this has already been posted or not, but here's an outline of the robot face from the Trailer. The facial features actually appear to be more of a "holographic image" as opposed to a mechanical construction. Either it's like that as it's just a trailer & not the finished article or it's more an I-Robot theme for the face! Either way, my opinion is there's no way this is Megatron. I think it could be Rumble or maybe Frenzy.... or the Movie Soundwave.... they all have similar facial features to this.