However, even while the world goes into cloud, I like the dashboard widgets and found them to be pretty useful for many types of tasks. Anyway, until the computer is not the browser (it might be so, someday, though), there is a market for desktop software.
As it comes out, you can start doing them pretty easy by using Dashcode. It's still in beta, but gave me a pretty solid impression and made them process very clear for me.
Literally, it takes only few steps to produce sample widget. More then that, you can also test it right within the Dashcode environment. I was prepared for overriding the dashboard into debug mode and placing widgets on the desktop for further development, but using Dashcode makes it much easier. (I'm still going to place some widgets on the Desktop anyway.)
The only thing that Dashcode doesn't make very easy, is how to get the link to the actual widget package. I found it to reside within the project's folder, but it looks like this is something I could just click and get from the menu bar.
Now I'm going to keep the designers and developers busy with nice picture and functionality, so I can continue playing with the widget.