desktopx pro just really "took off" recently with the release of 3. I think stardock could probably do more to promote desktopgadgets, but honestly until they have a lot of content they probably don't want to draw a lot of people in only to have them disappointed and not come back.
The pro version of desktopX is monstrously important, imho, and has been shamefully overlooked so far. This is a really, really powerful program that could change a lot in the way of small app development on the Internet. Only a small number of people are using it, and they really haven't delved into what it is capable of yet, imho.
I'm working on a couple of things and keeping a diary while I do it to post on JU. I'm excited about what the app can do and I think a lot more people will be soon as well. I think you'll see desktopgadgets take off when more people discover what desktopx pro is capable of.