Continuity mistake: During the battle with Green Goblin, when Gwen Stacy is falling through the clock tower, there are dozens of gears and other pieces of various sizes falling with her. However, when she lands, only a few small gears and pieces land alongside her - all the other debris that were falling have seemingly vanished. (02:01:20)
Suggested correction: That part of the scene is SO dark that it's really hard to tell; they do show some gears and pieces land after she does and there are some gears and pieces next to her when he walks to her. I wouldn't say there's none, but I'd say it does seem a disproportionately low amount considering how many giant gears were falling.
Given that even you admit in your correction that the number of gears seems disproportionately low (which it is - we only see a few small pieces landing when there were dozens and dozens of pieces in different sizes falling), I think amending the wording through a word-change is a better option than trying to correct the mistake itself. Because there is still a mistake here. Going to go ahead and do that after I post this response. (Might take a few days to change, though).
Continuity mistake: In the scene where after Peter gets his diploma and has a chat with Gwen, he is carrying a backpack on both shoulders. As the scene continues it switches to one shoulder then both several times. (00:15:50)
Continuity mistake: After Peter gets his diploma and has a chat with Gwen, the sun changes between shots.
Continuity mistake: During the battle between Electro and Spidey, the chip on Electro's head swaps from being on the right side to being on the left. It is specially noticeable when Electro overloads.
Continuity mistake: When Peter and Harry chat by the river and Peter jumps to the other side of the railing, his left hand is either atop or below the railing, depending on the shot. (00:41:30)
Continuity mistake: When Gwen dies, the position of Spidey's left hand is inconsistent in almost every shot: Moving between her temple and cheek back and forth. Also, when he says "Stay with me" his right hand suddenly appears / disappears randomly around her head. (02:02:05)
Continuity mistake: Peter is in bed watching the closet with his dad's briefcase inside. He stands-up and his earplug falls out, but a shot later it's back in. (01:01:10)
Continuity mistake: Peter opens the closet and throws a red jacket on top of his dad's briefcase, then closes the closet. Several shots later, when he opens it again the red jacket is gone. (01:00:05 - 01:01:05)
Continuity mistake: After Electro launches Spidey against the police car, the huge dent on the door gets smaller between shots. (00:55:40)
Continuity mistake: After Aunt May takes a picture of Gwen and Peter they're standing side by side. A shot later they're a meter and a half away from each other. (00:15:55)
Continuity mistake: When Aunt May takes a picture of Gwen and Peter she places two left fingers on the camera. When the angle changes there's just one. (00:15:50)
Continuity mistake: After saving a bus, when Spidey confronts Rhino the big puddle beside him disappears between shots. (00:13:45)
Continuity mistake: When the fake pilot stands up to punch Peter's father his parachute disappears. (00:05:30)
Continuity mistake: While Rhino is getting webbed by Spidey on the street, the sun changes between shots. (00:13:55)
Continuity mistake: When the Statue of Liberty tells Spidey "Nice outfit!" the people in the background are in different positions at the cut. (00:21:20)
Continuity mistake: When the kid dressed like Spidey slips through the barricade, look at his mother in close-up. To her left (right of the screen) there's a guy with white hair that breaks into a sound reminiscent of the famed Aro's Laugh. In the next shot, the guy is in a different position, to the right of the previous position, closer to the asian guy. (02:10:25)
Continuity mistake: Spider-Man leaves the "I love you" message to Gwen on Brooklyn Bridge, and on the tower of the bridge you can see the American flag. When the bridge is in the background later, the flag is gone. (01:45:15)
Continuity mistake: When Electro pierces the chest of the head of the security, the guy falls at a certain distance from the chair and table of the office, but when Harry saunters off to his body to grab his gun, the dead guy is right by the furniture. (01:40:05)
Continuity mistake: When Peter pulls the boot of the costume under the cover to prevent May from seeing it, you can get a good look at the stack of books he's going to trip into a few seconds later. In fact, you can still see even as he trips, that the stack includes the famous leather bag from his father. He doesn't knock it to the floor when he trips, but the next shot just shows it on the floor anyway. (00:23:25)
Continuity mistake: The little bullies are pushing the wind turbine kid against the fence; they literally have their fingers inside the links; they look up and notice Spidey, barely move very slowly, but a moment later they are much further back in the alley giving him a solid few meters of space where he lands. (00:20:35)