When the triplets are sleeping in Central Perk, Frank Buffay Jr. Jr.'s position on the couch changes between camera shots.
The previous episode ends in a cliffhanger, where Ross walks in when Joe and Rachel are kissing. Rachel is the first to break the silence, saying, "I am so sorry...". When this episode begins from the moment Ross walks in it is Joey who breaks the silence. However, this is because the first few seconds of the episode are intended to be a recap and not a direct repeat of the previous episode.
Ross burns his hands on the fajitas bowl. Later on when he's making a toast his palms show no signs of it, not even a little red, yet it burnt him enough to be sore the next day after high fives joey.
Coleen tells Chandler where the bathroom is in her apartment. Her line is 'down the hall and to your left.' However, she gestures to the right with her hand.
At Ross' place while having margaritas, Ross suggests they all should take a trip. After that he asks where they could go, but his lips don't move. The sound track is clearly originally from the next shot.