The Wreckers: Leadfoot - Roadbuster - Topspin
We know all three of these characters will appear in the film, as they were both seen on the set AND have voice actors assigned to their roles. Just like Sentinel Prime, they most likely have remained dormant in the Autobot Ark which crashed many years ago - where they stayed until reactivation.
Autobots: Backfire - Icepick - Thunderhead - Sandstorm
These four robots could be the new Arcee of Transformers: Dark of the Moon and like her will most likely be seen and not heard. The toys come from the MechTech Human Alliance line so don't be surprised if you catch glimpses of them working in unison with military personal - to protect the planet from the Decepticon invasion.
Decepticons: Crankcase - Crowbar
Even though most Autobots in the comics were ground vehicles (with Decepticons ruling the air), Crankcase and Crowbar will join Barricade and the new Dreads in the ground assault. It looks like Optimus Prime's right-hand men, Ironhide and Rachet, will have their hands full with these new characters.
Bumblebee's New Look
This is purely speculation and rumor but if the toy line is any indication then Bumblebee could receive a new paint job by the end of the movie. While Bay decided to ditch the iconic yellow Volkswagen Beetle for the modern Chevy Camaro he did keep Sam Witwicky's friend painted the yellow color Transformers fans are most familiar with. Even in this new yellow-on-black color scheme Bumblebee looks pretty slick.
That said, we've seen plenty of footage from the film to indicate that Bumblebee remains true to his yellow roots - so it's certainly possible that this is just a cool color variant.