Continuity mistake: In the battle scene at autobot city, Megatron orders Soundwave to jam the transmission that Blaster is sending to Optimus Prime. When Soundwave ejects Rumble, Frenzy, Ravage & Ratbat we see them flying through the air transforming simultaneously and and both Rumble & Frenzy are coloured the same (red & black) when Rumble is supposed to be purple.
Continuity mistake: Towards the end of the movie, Spike and a few autobots are about to be dropped into the vat of acid. When the view is from above the vat, look carefully to see Daniel already in the room standing in the very spot he will shoot the cover from. However, a frame or two later shows Daniel running into the room.