Megatron is missing his arm cannon when Starscream confronts him in their shuttle. True enough, he lost it in an earlier clash, but he was shown having it in other shots.
Ironhide can be seen with his blaster on his back before he activates it. It only rises from inside his back in the following shot.
As the Decepticons board their new space-ship, there are several Seekers (Transformers who share Starscream's design, albeit with different color schemes). As they march forward, all of them suddenly change their colors, some even twice during the shot.
When the Decepticon ship launches into space, Mirage can be seen standing with the rest of the Autobots on Earth, yet a few shots later he is shown to have stowed away on board the ship in order to sabotage it.
When Soundwave says the line; "Energon cubes still functional." He is shown with an Autobot symbol on his chest.
Hound skirmishing with Rumble is actually re-used animation from the previous episode. Since in the last episode, they had been fighting underwater, you can see some bubbles rising. In this episode, the bubbles create a goof, as the scene takes place on dry land.
The Autobots react with terror to the Decepticon ship rising up from Earth. The shot has only one problem: namely, the artwork of the Decepticon ship missing.
In the same scene, there is one shot in which the animation cel of Megatron's head was placed behind the cel of his torso. Because of this, his back cannon seems to be covering a small part of his head.
When all the Autobots transform and roll out victoriously, they are drawn a lot more "chubby" than usual. As Prime drives along, we can see the top of his trailer hasn't been fully drawn.
The clips in the recap segment near the beginning haven't actually been taken from the previous episode itself, but feature unfinished and often erroneous animation. For instance, when we see the clip of Megatron activating his Energy Mace, a giant tear appears on the screen.
Optimus Prime barely recovered from an explosion in the last episode that sent him tumbling down a hillside. Yet in this episode, he simply shrugs off an impact after falling out of Earth's orbit. This crash should have devastated him.
Mirage parachutes out of the Decepticons' space ship to land safely among his Autobot pals. Given the altitude of the ship, when he jumped out, it would be near impossible to land at the spot the ship took off from. More likely, he would have landed miles and miles away from them.