Continuity mistake: The part in Bruce's hair switches sides after he's on the wall saying 'love me' at the daycare center.
Factual error: At the very end of the film Bruce is reporting on a drive for blood donors, and Grace leads him over to the booth to give blood himself - he is even wearing a tourniquet. However, he is supporting himself on a walking stick - he is not fully recovered from the injuries he received when he was run over, which happened when he was hit by a moving car - injuries which left him clinically dead. There is absolutely no way that a person who has suffered life threatening injuries and has undergone the (inevitably) intensive drug therapies and surgical procedures involved while under treatment in hospital in the fairly recent past would be allowed to give blood. There is no way that the Red Cross (or the US equivalent) would want to encourage people who have recently been hospitalised to try to give blood. Not only would that be the height of irresponsibility, they would be wasting precious resources and staff time turning away people who would not be allowed to give blood.
Other mistake: Early in the film, Jim Carrey is watching TV during a sports segment. He is watching Channel 7, the station he works for. This clip they showed was of actual WKBW sports director John Murphy. The clip they showed was taken directly from a real WKBW newscast, with the authentic news set, and graphics. However, when they show a clip of Ch. 7 News later, there are completely different graphics, and a completely different news set, both made for the movie.
Continuity mistake: After the riot in the streets of Buffalo, Bruce meets up with God again in the Omni Presents building. They discuss how everything is going wrong. At the close-up shot of Bruce's face when he says, "What do I do now?" the frame is flipped. You can tell this because his hair is parted on the wrong side and his nose looks different. (01:15:20)
Factual error: Even God could not arrange for everyone to win the lottery at the same time. Many people use their favourite numbers, and many syndicates play the same numbers every week. There is simply no way - God or no God - that every ticket could win, because there is no way that every lottery ticket could be the same. The tickets cannot have been magically altered - many people know the numbers they have played and would not think they have 'won'. Note that the protesters are complaining that they won the lottery but got back less than they paid for the tickets they purchased. That is only possible if everyone who bought a ticket won, as all lotteries pay out a percentage of the total amount of money taken in from ticket sales.
Continuity mistake: When Bruce and Grace are in the kitchen, and Grace is commenting on how she thinks her boobs have gotten bigger, Bruce is squirting ketchup onto his plate. When he first does this, the ketchup goes everywhere, all over his plate. It then cuts to Grace and then back to Bruce, and the ketchup is now in a nice, neat pile. (00:44:30)
Revealing mistake: In the scene with the accident, the car already has bumper damage just before it hits the pole. (00:21:00)
Visible crew/equipment: When Bruce goes back to the building toward the end of the movie looking for God and finds it deserted, as he runs through it, you can see the shadow of a figure (a crew member) on one of the columns on the left. It even slightly moves as he's approaching the ladder as if trying to duck away from behind. (01:13:55)
Suggested correction: This is definitely God's shadow. It's exactly where he appears a little later. So it's not a crew member, but a continuity error because Bruce must have seen him when entering the hall.
Continuity mistake: When Bruce is seen driving his car across the bridge after his first meeting with God, the hood of his car is no longer dented from the accident. (00:31:30)
Continuity mistake: Right before Bruce changes into the cloud shirt and black pants from the store, the people in the background disappear. (00:36:45)
Continuity mistake: The scene where Bruce is putting a picture in the photo album, the right side of the page is empty. But when the shot changes, the right page now contains pictures. (01:16:40)
Continuity mistake: When Jim Carrey parts the traffic and when the camera is on the side of his car and he starts to go, look all the way down the road you could see a person crossing the street but when it shows a sky view of him driving there's no one there. (00:45:45)
Continuity mistake: When Bruce returns home after getting God's powers and sings "What if god was one of us" in the door, his mouth is wide open as he sings 'home' but in the next shot where we see him from behind, his mouth is closed even though he's still holding the note.
Other mistake: When Bruce is responding to the e-mail prayers on Yahweh., you can see the prayers don't change, they just repeat the exact same requests in the exact same order. (00:59:35)
Continuity mistake: When Bruce is doing his live report after going on air, he has a very shocked expression. But when we look at the live screens (in the studio), they show footage of him smiling earlier. (00:14:40)
Continuity mistake: When Bruce talks to his boss, after the boss buys a sandwich, Bruce's shirt collar is tucked under his jacket. However, in the next shot the collar is straight. (00:10:30)
Continuity mistake: When Grace visits Bruce at the hospital her hair keeps changing between tucked behind her ear and hanging down. (01:26:35)
Continuity mistake: When the pager goes off the first time Bruce takes it out, holding it in his hand. When the camera angle changes he is holding it by the edge. (00:22:25)
Audio problem: At the classy restaurant, watch the man playing the drums. The brushes that he's supposedly using to play the snare drum are an absurd 5-6 inches higher than the drum, making it obvious that he wasn't really playing, and that the music was dubbed in. (00:53:15)
Continuity mistake: In the diner, Bruce is looking out the window and the waitress walks up to him. You can see the two coffee cups on the side of Bruce's table next to each other. When the waitress asks "Coffee?" and the shot changes, one of the cups is suddenly at the centre of the table. (00:31:15)
Suggested correction: Bruce could simply alter people's tickets and then alter their memories too. He wouldn't be affecting free will, since they still made the choice of what numbers to pick, Bruce just altered their memories to make them think they did something else. They're not protesting they got back less than they paid. They won $17 dollars each. I don't know how much a ticket costs in Buffalo, but I bet it's less than $17.
Suggested correction: Since Bruce was given God's powers and a lot of people were praying to win the lottery, he could have simply altered the numbers on their tickets.
Not only that, but one guy was complaining that he only won seventeen dollars.