Continuity mistake: The "Staff Writers" door is backwards. In other episodes the door opens up to the right, not to the left. Also the door is a dark color normally, unlike this scene in this episode where it's a light color. (00:19:41)
Visible crew/equipment: While Rob is sick in bed he's just about to grab the phone near the end of this episode you can see a big shadow of a giant camera in between the back of the TV set and a stage light behind the camera. (00:21:22)
Other mistake: Laura tells Rob "oh you don't smoke!" But in several (double digit) episodes Rob not only has a lighter but also a cigarette in his hand or mouth. One episode while he and Laura are illegally about to eavesdrop he puts out the cigarette on the speaker causing the speaker to turn on and they start eavesdropping again.