I think the biggest change has been in the number of people who actually take an interest in how the picture looks...
Bear with me and I think you'll get my drift.
More and more people now own a computer with even the most basic software they can edit an image..even if it's just a crop or red eye removal.
Looking back a few years those of us who managed a darkroom set-up were looked upon as "geeks" (though I suspect the word probably hadn't been intended for us).
So technology has given the "masses" the opportunity to take their hobby or pastime further, in this case photography and therefore I would have to say aye..it has improved the art..though not necessarily the content...sadly