At the flower market, when Reed meets Kelvin and at the agents office when Paula initially speaks to Liz, the characters speak, and we distinctly see their mouths move, but it is very clear that they are not saying the words that we hear.
On the bridge when Alphonso is fishing and talking to Reed, the camera goes back and forth to both sides of Alphonso. Alphonso is holding the fishing pole different each time, on one side he is holding the handle and the fishing line and the other he is holding the handle and the pole, not the line. Also, importantly, he is using a bait-casting reel and the proper way to keep the line from unreeling is to place your thumb on the spool. The way he is holding the reel is like that of a spinning reel.
When Holden is served a candy heart sucker on the plane, he gently pushes it away with his finger on the very end of the stick - quickly followed by a close-up showing him pushing it with the same finger halfway up the stick.
When Edgar is telling Grace about the possibility of having only one sex partner for life, we see Grace's cell phone on the table. When Estelle gets up, Edgar follows, Grace's cell rings and is no longer on the table as she pulls it out of either her right pocket or a handbag.
At the beginning of the movie when Kelvin is talking to Susan during the morning news broadcast, a map with the day's forecast shows a high of 90 in Sacramento, highly unlikely for February 14 in the middle of winter.
When Reed tells Julia that Harrison stopped by the flower shop to place his order, she doesn't question it even though Harrison had falsely told her over the phone he was pulling into the airport to go to San Francisco in an earlier scene.
In the first shot at the end of the movie when Alphonso and his wife are swinging on the swing, his wife has a long clear store sticker on her shirt (looking at it would be left side) when the shot resumes, it is no longer there.