One thing I heard from more than 4 tables is that Spring is not nearly as popular as the Fall meet, so take that into account. The discussion overheard was that winter is the time more people are thinking trains as well as thinking approaching Christmas. I always attend in the Spring as my birthday is in April and it's my little celebration.
I attended as a guest for the second year in a row. There were a few vendors having "going out of business" sales but many looked strong. It does seem that modern is more popular now than old PW equipment.
Prices at some vendors were lower than I've seen in previous years and even though I have no room left I almost "had" to pick up more trains though my visit was for layout building materials.
As far as demise of the show that is more up to the vendors I think. There were more trains and model supplies there than I ever see in one place. For me, seeing items in person and skipping shipping costs is worth the trip but I live within driving distance of York.
Thank Heavens for the modular layout groups as that is where I saw the most kids and parents. Great job pulling new folks in.