Continuity mistake: When Ryan is lighting Marissa's cigarette with his, at the start of the shot it's full, then the shot goes to Ryan and it's still full. But then the shot goes to Marissa and if you look at Ryan's cigarette you can see it is almost all gone. Then the shot goes to Ryan and the cigarette is full again.
Trivia: Seth is surprised that Summer has read the book "Madame Bovary". She explains that it's the favorite book of patient Tom Shales, who is incontinent (lacking normal voluntary control of excretory functions). Tom Shales is a Washington Post critic who blasted "The O.C." in his review.