The fashions and hairstyles in the movie are horribly dated. But beyond that, Jaws is timeless.
It isn't even that the movie is scary (which it is). Jaws is a film that purely cinematic. It a audio/visual spectacle that is thematically rich, character intensive, written to perfection, and paced to brilliance.
It is also the emblem of how restrictions are the friend, not the enemy of creativity. Spielberg famously took the production's greatest weakness (the failure of the mechanical shark) and turned it into one of its greatest strengths. It's easy for masters of visual storytelling to rely on what is on the screen rather than trusting the audience with what is off the screen.
And that score that starts to sync with your heartbeat as its primal power beats its way into a frenzy cannot be duplicated.
I have never seen it on the big screen and I'm going to the theater to see it tonight. I cannot wait!