Without further ado, here is a link to the official teaser trailer on the Seibertron.com YouTube channel:
We get to hear Peter Cullen as Optimus prime and Ron Perlman as Optimus Primal who spends quite a bit of time in his gorilla mode with only a brief look at his robot mode at the end. That goes for the other 3 maximals in his movie (Rhinox, Airazor and Cheetor) who are seen more in their alt modes, at least in this trailer. We also get a very good look at Mirage's robot mode and his power which does have a G1 theme to it. We also see Arcee and Bumblebee very well. We get to see the shot of Arcee hanging onto Wheeljack's van alt mode which was previously shown to industry insiders.
The villains are less obvious in this trailer though we do get a good look at Battletrap in both of his modes. You'll let us know what you think!