The official Transformers Facebook page has recently updated with the first promo video for the upcoming Transformers : Combiner Wars cartoon series. Keep in mind the final product will not be a stop motion production like what can be seen in the trailer. The promo features Optimus as he is traveling on a battle destroyed Cybertron. As he sees the destruction the “Combiner Wars” has caused he then confronts Megatron leading to the final onslaught between the two warriors. Transformers : Combiner Wars will premiere exclusively on the GO90 network on August 2.
EDIT: The trailer has also been posted to the official Machinima Youtube channel.
Source: Transformers Facebook