When one of the 2 jeeps explodes, the front side of the jeep is on fire.
When they hunt for the snake and Pinkus stays behind them, only the rear side of the jeep is on fire - the front side is shiny white and clean again.
In the scene where Amanda is cleaning up after having fallen in the mud puddle, she is experiencing flashbacks of all the deaths caused by the anaconda. However, she was not present for the death of Darryl, the anaconda's first victim, and therefore wouldn't have a visual memory of his death besides seeing him post-mortem when she and the Professor were gas mask clad and hunting for the snake.
When they arrive at the farmers place, the house front door is open. When they walk up to examine it, the door (as well as the thin mosquito door) is now closed.
During the scene where the farmer is looking for his goat, he falls through the floorboards in his hay-barn and is visibly covered in hay when he lands on the floor. However, in the short time between then and when his goat scares him, not only has he completely removed the hay from on top of himself, but it has completely disappeared without trace.
After Amanda falls in a mud puddle, in the next scene she is seen washing her face in the sink of the farm house. Her hair and clothing are both clean and not out of place or stained at all.
It is stated that the enclosure housing the snakes contains 3 inch thick glass. However, after the glass is broken, there is a shot where you can clearly see the width of the glass is not even an inch thick.
The "SAT phone" is actually a Nokia 92xx Communicator. The earpiece is just above his forefinger.
When Amanda is burning her files at the end, a clear shot of one page is seen. Not actually secret snake formulas, it is in fact a collection of chemical reactions one might see on an exam for first semester organic chemistry (elimination, bromination, ozonolysis, hydroboration, etc.).
During the scene where they are searching for the snake in the abandoned warehouse, there is electricity still on.
When Amanda is in the van after it crashes, the camera first pans to the snake above her. When the camera pans back to her, a crew member can be clearly seen walking past through the window behind her.
After the Jeep crash in the forest, Amanda is confronted by the snake from above. During this scene, a crew member can be seen walking past through the window behind Amanda.