So I went on the forza forums, and THIS was on it...

What can be seen is the following :

1. An expansion to the car roster of the eliminator.
2. A picture of (Dutch?) police officers (prediction follows).
3. We know we will get 4 new cars this update.
4. Some more eliminator circle stuff on the whiteboard.
5. Some writing (prediction follows).

Predcitions :

For the police picture, I can think of one of 2 things : more police lights made availible for cars or a new Dutch car comming to H4. Wich car you ask? That would be most likely be the Savage Rivale, wich was spotted on the leaked list from a while ago. Allthough it isn’t 100% guaranteed, this list is the only source in terms of cars that we haven’t right now.

Next, the writing on the whiteboard (very difficult to read). The things that were readable were :
“heavy weight upgrade peak”
“respond to Isha a taxi”
“check vulcan speeD”
“Decide… unreadable text“

Most likely, some of these could be car hints.
“Heavy weight upgrade peak” could relate to a heavier vehicle… And since the Dakar AND forza Dakar are on right now, wouldn’t it make some sense that this vehicle would be a Dakar car? The option on the list could be the Nissan car from the 2004 edition of the rally.

“Check vulcan speeD” could be a reference to the AMR pro package of the Aston Martin vulcan. This is a car that I find somewhat pointless to add since the regular vulcan isn’t that much different.

On the forza forums however, everybody says the capital D letter could refer to Initial D, and everyone knows what car that would most likely be… But I don’t really buy it since there could be still people that never heard of it.

That’s all I could find out (with some leads of from the forums). If you guys have any more predictions or leads, then please put them in the comments.