Re: Transformers 4 is going to be AWESOME.
AFAIK, not sure...
There was an unconfirmed toy box which revealed schematics of the dinosaur bots. There was also a guy on TFW2005 that posted some images of Prime, Bee and a T-Rex head. I don't think it was ever confirmed that they were real. From those images, a guy on TFW2005 called 'Tunakaan' has made some sublime fan art that has been stolen by various websites around the net that claim them as either official images or their own work.
*Insert clever, witty movie quote here*