Article: Ten Things I Learned from the "Robots in Disguise" Trailer (Page Two)
6. Grimlock (or a 'bot that seems based on his design) will be part of the team
The trailer shows a dinosaur Autobot with a robot mode that has classic Grimlock stylings from the parts of the shoulders being parts of the beast mode legs to the shape of his head, though here he has a mouth instead of a mouthplate.
7. There are a "couple hundred" Decepticons running loose and many seem to have "beast" like qualities.
Fixit mentions there are a "couple hundred" Decepticons that need to be hunted down. The couple that are shown in the trailer appear beast-like. One looks sort of like a wolf, the other a shark (and of course there's Underbite). This also suggests that they are not a cohesive army (at least not yet).
8. The show will feature traditional transformations
One question that comes up now and then (perhaps a bit of a collective fan reaction to the days of "Beast Machines" and more recently "Age of Extinction") is whether the show will feature "traditional" transformations with parts moving and shifting and some variation on the old G1 transformation sound. Based on this trailer it looks like those are intact. We get to see both Underbite and Sideswipe do full transformations (and a partial one from others).
9. The Autobots will focus on melee combat
In the trailer it appears the Autobots are mostly armed for melee combat between Bumblebee holding a staff and Sideswipe holding a sword. "GrimlocK" looks like a bruiser and only Strongarm appears to have a blaster. This kind of fits in theme with the idea that they're fighting "beasts" so it should be interesting to see how it plays out.
10. New humans are part of the cast
Instead of bringing back Jack or any of the other humans from "Transformers Prime", it appears a father/son team are the new human proxies for the audience. I confess that I would like to see perhaps an older Miko or Jack showing up in the show to offer some more continuity.