I don't know what's harder to believe - that the original Transformers series worked out a way to include robot dinosaurs, or that Michael Bay's Transformers series waited three whole films to finally include those robot dinosaurs. You'd think that would have been a day one purchase for him.
It hasn't been announced that we will for sure see Dinobots in Transformers 4, but look at that poster. It's basically the logo we already have - the image of a Decepticon mutated to such an extent that half his face has turned into the number four - only this time there's also a bunch of sand. Sand = dinosaurs. On top of that, the film's subtitle is Age of Extinction. Dinosaurs went extinct! Unless this is all leading up to the revelation of a Dodo Birdbot, I think we're finally going to get cinema's first ever shot of robot dinosaur testicles. They will greatly confuse Mark Walhberg.