Corrected entry: When George and June are going up in the elevator to play strip chess, we see him swipe a card in the elevator. This is presumably a electronic key, so that hotel guests can't stumble into his apartment. However, when Lucy runs out of the wedding, we see her press a button to go up, and then wait, without having to swipe a card.
Corrected entry: After George reads his speech to Lucy, she says it was fine except for "the split infinitive near the end." There was no split infinitive. (For example, "to boldly go" is a split infinitive; "to go boldly" is not.)
Corrected entry: After the stapler fight George drags Lucy into the pantry by holding her at the arms. The camera cuts briefly to June, and when it's back on Lucy and George he is holding her around the waist and Lucy is wildly brandishing the stapler at June. It's theoretically possible but looks quite wrong.
Corrected entry: In the scene where Hugh Grant and Sandra Bullock are in the car and stuck in traffic, it appears that it is raining. However, there is no rain falling on the windshields. When both characters get out of the car to run to the RV, they cover their heads, but again no rain is falling and they are not getting wet.
Corrected entry: When George and Lucy leave their car in the traffic jam, in one of the cars they pass you see George's brother and sister-in-law. This amazing coincidence has no further significance in the plot as they were not with them at the tennis club, and must have been forgotten to get edited out.
Corrected entry: In the scene when Sandra first meets Hugh to talk about the community center, if you look in the background you'll see that it's raining, but neither Sandra or Hugh is getting wet.
Corrected entry: In the scene towards the beginning when Sandra Bullock and Hugh Grant first meet and she is talking about the community centre, Sandra is wearing a singlet underneath a long sleeved shirt, however in the next shot she is wearing a short sleeved shirt underneath, then it changes back to a singlet again.