Continuity mistake: Following Rodney's step from the escalator on the red pedestal he is being scooped into one half of a wire-frame globe/ball. Two halves now (the other one has Fender in it) form an intact globe. A safety bar with a 'wooden' middle bit (like those on rollercoasters) suddenly appears. After their journey, when the ball splits back into two halves, the safety bar, which previously had mysteriously appeared, now has disappeared.
Continuity mistake: When Rodney steps on the escalator (a giant metal wheel with escalator steps), in the station of Robot City, you can see another robot standing on the step above him. In the next shot Rodney gets from the step on top of some sort of red pedestal. The robot on the step above him has now disappeared.
Trivia: A little nod to another Blue Sky Studios Production, "Ice Age". When Rodney is looking around Robot city, he comes across a red robot that plays hip-hop. As Rodney walks away nervously ("Uh, n-n-never mind"), pause the frame just before the shot changes and you'll see (on the left) a yellow, mechanical Sid. Sid is the sloth (and the main character) from "Ice Age". (00:15:25)