Jerry (Jerry Seinfeld) and George (Jason Alexander) are shown sitting on the couch. Jerry is on the left side of the couch - nearest the kitchen - before getting up and going to the kitchen. When the camera shows us George again, he's now sitting where Jerry was a moment earlier.
When George is in a store trying to prevent a costumer from buying a suit, he holds the jacket in his hands. The next shot, it isn't there anymore.
George puts his bowl of cereal down on Jerry's coffee table half-finished. The next time we cut to it the bowl is empty.
When Jerry is in the men's room and washing his hands, there is no water coming out of the tap.
When we meet Bob, the other shopper that wants the suit, he is wearing the suit. After George confronts him Bob walks back towards the fitting room. As he is walking the suit doesn't make the swooshing sound that it makes when George is wearing it at the job interview and the Diner.
The "Elaine" mannequin in the store is different from the one in the car. The eyes are pointed in a different direction and makeup is completely different.