These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Director Displacement: Michael Curtiz won the Academy Award for Best Director, but that's about all the acclaim he's ever gotten for this movie. Film historians and critics usually credit the producer, Hal B. Wallis, and the various writers (Julius and Philip Epstein, Howard Koch, and the uncredited Casey Robinson) for the creative direction of the film. At worst, Curtiz has been called a "journeyman hack" or a "hired gun", though he did have a very successful career overall.
Genius Bonus: Bogart's eyes are brown - not that viewers could tell that, since Bogart had appeared only black and white films until that point.
It Was His Sled - The plane scene and "We'll always have Paris" is... uh... kinda obvious. It's even the iconic scene shown at Disney's Hollywood Studios for its famous movies tour.
Memetic Mutation: A good chunk of lines from the film have become considerably memorable. Notable is "Play it again, Sam", but they don't say these words exactly.
Another notable line is: "I believe this is going to be the beginning of a beautiful friendship."
"I am shocked, SHOCKED to find that (insert not-so-shocking event)."
Narm: Sadly the awesome "Le Marseillaise" scene is partly ruined by the close up of Yvonne and that ridiculous expression she makes as she is singing along.
Justified: That was possibly the actor's real reaction. The movie was shot in 1941, when France was still occupied by Nazi Germany, and the movie was cast with many refugees with memories of their home being invaded fresh in their minds. It would be similar to a movie about 9/11 shot only months after it happened with some of the actors having lost family in the attacks.
Watch It for the Meme: Watch it for any of the most famous lines; possibly even watch it for the Beam Me Up, Scotty!, as many people now realize that it isn't "Play it again, Sam."
In fact, the majority of this movie's most famous lines are in the end scene, causing it to practically overdose on Memetic Mutation in the last ten minutes or so.