As prices come down and users learn how to take advantage of player capabilities, use will grow. It's going to be a while before VHS and laserdisc get replaced by CD-ROM and DVD because teachers have learned that VHS and laserdiscs still work after more than a decade of use, but the computer products of the same vintage are now obsolete. The complaint I've heard about laserdiscs is that the clips are often too short and not worth the effort it takes to play them. My own feeling is that once you learn how to use the clips interactively, i.e. to get the students to observe and think about what they're seeing, they work really well. Unfortunately, I haven't found many people that have learned to use them interactively.
Most people are still in the passive TV watching mode.
If the subject of interest is complex and zips past the viewer in a few seconds in one viewing, it's difficult to learn much from it. Repeating the observation in slow motion with new questions from students, stepping through difficult parts, or studying a single frame in detail really helps students understand better. Finally, the quality of laserdisc images is far better than computer video and VHS if you have a big screen to project it on and properly adjusted equipment. I show it to the students the first time at full speed and then give them a couple minutes to write a description of what they saw. Then I have them compare their observations with their lab partner to see what they may have missed.