At about 28:15, Data is in the holodek, holding a taxi cab in place that was trying to run him over when he was trying to depolarize power to one of the newly created computer nodes. When Troi calls him, he holding the front bumper of the cab with his left hand, and the tires on the cap are squealing from not being able to move. Data says he is ready to depolarize the power grid, and the camera angle changes to the view of the manhole he is reaching into, when his left hand comes into view for a second, with the sound of the cab still stuck and tires spinning.
After the console explodes in front of Geordi, it throws him a fair way but there's not a scratch on him.
When the train passengers are having the party at the end of the show, Worf, Troi and Data are in attendance and each has a glass of champagne. When the rest of the holodeck characters disappear, they are still holding their glasses. When the holodeck scene disappears, the glasses of champagne that they are holding should have also disappeared.
Data is shown working in the uncovered manhole to bring down the power grid, after which Geordi tells him to stop what he is doing. The very same footage is reused when Data brings the power grid back online.
As Data is performing The Tempest in the Holodeck, a small piece of paper is briefly seen attached to the book he's carrying, and at times during his speech, you can see Brent Spiner reading from it. In the next shot, it's gone. The paper is most likely Spiner's Prospero lines.
When Data is depolarising the power grid while holding the cab back with his left arm, the scene cuts to a view from over his right shoulder. There is a brief moment when his right arm is moved back to show his left hand. Since his left arm is no longer holding the cab, it should be in motion running him over. Even so, the wheels are still heard burning on the road as if still being held back.
During the earthquake, when the brick wall collapses behind Troi, a member of the crew is briefly visible behind it.
When Geordi and Picard are on the bridge talking about the events in the cargo bay, there's a cable lying on the deck, to the left.
When Picard and Data are looking at the oncoming train on the holodeck in the teaser, a black wall directly behind Patrick Stewart is clearly seen.