Just found this posted on electrek.co (from reddit): "The vehicle seems to be equipped with at least 6 cameras and 2 different sensors. 3 forward looking cameras, one on each side and one in the back." - it looks more like 5 cameras in the front, if you include the stereo cameras fitted in the middle of the screen under the autopilot camera. Wouldn't be surprised if this was related to DrivePX (& Model X) testing, or this Bosch system which also uses a stereo front camera. Not sure if this is new info, but couldn't find anything related after searching. More pictures over on Imgur.