The quality can't be improved much.
I think you aren't that aware of the latest techniques as even older movies often look superior on blu-ray.
Some great examples that I know of (as I have them) are Patton, Apocalypse Now, Gandhi, Butch Cassidy and the Sundance Kid and the Alien films. Especially the first two Alien films and Apocalypse Now, who look on blu-ray as if they were made a couple of years ago. And I'm not joking.
Even The Godfather films are superiour on blu-ray, although less impressive than others I must admit. But that had to do with the horrible state of the original roll films.
If you're a movielover, blu-ray is definitely an improvement, although for most people a DVD will be good enough.
