Rewatched Jaws and was sort of surprised at how strong the screenplay for it actually was. All the details in the movie really seem to count for something. It runs just about the right length at 125 minutes and none of it really seems to be a waste; there isn't *much* of a plot, but it isn't underplotted either.
There are bits of interesting early 70s sociology to be found too, like the Dreyfuss character being a newfangled intellectual techno-geek, or the girl who dies at the beginning being part of a group of longhaired free-living partygoers. I mean it's no Long Goodbye but you take what you can get.
Also some of the most harrowing death scenes ever, as in "I really don't like to think about that happening to me, how painful." By contrast the deaths in Jurassic Park are all corny and stupid (and toned down from the book--now I want to read the book.)
It's interesting to think that this is the movie that started summer blockbusters. Did it feel like that in 1975? I wouldn't know...