Continuity mistake: Ross comes into Chandler and Joey's apartment to ask the guys and Rachel what they are doing in four weeks, the Magna Doodle behind him is blank. We cut to Joey checking his diary, cut back to Ross, and it now has "get out" written on it.
Continuity mistake: There is a scene in the guys' apartment where the phrase on the Magna Doodle keeps changing. Joey is complaining to Chandler about having to stay awake all night for a sleep study. Rachel and Ross then enter the apartment (at different times) and Ross announces he is getting married to Emily in a month. In some shots during the scene the Magna Doodle reads, "get out!" in other shots it reads, "Poop." (Widescreen).