In the scene where Zach tells Lane he's going to be playing guitar for 'Vapor Rub', you can see Lane take the bananas out of the shopping bag twice.
When Lorelai and Rory are sitting in Rory's bedroom talking about her future, Rory's ponytail changes from being on her back to pushed forward.
In the final scene with Lorelai and Logan, there are two take out boxes on the coffee table. When they sit at the couch, one box is open full of fries, the next is closed. When they show the boxes again, they are both closed.
In the opening dream sequence, when Lorelai walks out the door to go to Hawaii, Rory's bangs are all pushed to the side. However, in the very next shot, when she goes into the kitchen, they are positioned impeccably in front of her face.
When Luke and Zach are at the diner, right after Zach says ''Why am I even asking?'', his head position changes very suddenly between shots.