When Shirlee is on the Zim Zimmerman show, Zim asks her if she thinks her advice could potentially be harmful. When she is responding, the camera operator is seen walking closer to allow the camera to zoom in on her. Yet when the scene cuts to the control room, the cameras on Shirlee are all steady, not zooming in.
When Jack drops Shirlee off after their date, they pull up in front of her hotel. In the background, a sign for a cafe' says Open 24 Hours, but look closely: the cafe's interior is completely dark, indicating that it is closed.
Alan says that his and Shirlee's secret will be between "you and me and the lamppost". The saying is "you, me, and the fence post," the implication being that it's a conversation two neighbors are having privately over the fence between their yards (the fence being the only other thing to overhear them).