If I recall correctly the Laserdisc set included a soundtrack CD and a novelization (book) of the film. I'm glad they're including the full 2-hour version of the Laurent Bouzereau doc that appeared in the Laser set (but omitted from the 25th Anny. DVD). Other than this, I don't know what else might be omitted for this new Blu-ray. That new feature-length doc might make up for any missing material IMO.
The soundtrack CD was the same content as the original LP -- not from original tracks, but an arranged-for-LP modification. (A "real" soundtrack CD with all the actual tracks was released a decade or so ago, and it's stunning.) The book was the then-current paperback edition of Peter Benchley's novel. There was no novelization of Jaws
I still love my collectible LDs, but I'm sad to say it's probably time to let this one go, and reclaim its coveted two linear inches of shelf space. It was an impressive CAV set, and like you said, for a while it had the only complete version of the documentary. But unlike the REALLY superb sets (e.g. My Fair Lady
, Sound of Music,
the Pioneer Special Editions), which included much more of additional value, that's all there is. Now that I think about it, I guess I'll be saying the same about the E.T.
set. And yes, that makes me a little sad.