Thanks for confirming this issue.
My theory is that for old movies, BD would be a big improvement if you're comparing the BD with the old SD release. But if you're comparing the BD and the newly remastered SD of the same catalog title, the BD would still be better of course, but I guess the improvement would be only minimal.
However, I also think that BD is capable of giving us a big improvement over the remastered SD for old movies as long as the catalog title was originally shot in large-format 70mm film.
For example, the BD might be much better than the latest SD version of
2001: A Space Odyssey, since that title was filmed in 70mm. I think I'll buy that title one of these days.
Ben Hur and
Lawrence of Arabia might also look great on BD when they come out.
Therefore, only he new movies made within the present time frame will look good on Bluray like Avatar, otherwise, it's much better to stick with the DVD versions of Jurrasic Park, Inidiana Jones or any of the good really good Criterion titles.
If you want to stick with SD DVD for Jurassic Park, you will have to get a remastered DVD when it comes out, because the current DVD release is really bad.
My copy of Jurassic Park looked great on CRT TV, but it now looks awful on my flat panel.