Minor Plot hole: All the Toys at SunnySide are filmed 24/7 and modern camera systems record everything on tape. It is far-fetched to believe that no one in the past years has not seen any footage of the sentient toys talking to one another.
Minor Plot hole: Near the end of the movie, Lotso is trapped under some large object, to which woody reacts to try and save him. Woody grabs a metal golf club, and uses it as a lever to free Lotso. While woody is attempting this, the golf club slowly rises and starts to accelerate upwards. Buzz then jumps down and uses his weight to lower the club. So at that moment it has been established that the combined weight of woody and buzz will overpower the attractive force of the magnet, yet once Lotso is free, all three of them, holding onto the same club, fly upwards to safety. (by Andy F)
Minor Plot hole: How did Slinky get down from the Magnet ? It was still clearly in operation yet slinky is with all the other non-magnetic toys on the ground. (by Andy F)
Plot contrivance: When Buzz leaves the caterpillar room on the first night, he follows the villains into the vending machine without being seen. But since a Monkey toy was in charge of watching the cameras every night, this would have been very unlikely.