Plain old drag and drop on desktop computers, which I guess has been around for at least 30 years by now (disclosure: figure out of the air, not researched) sti

Plain old drag and drop on desktop computers, which I guess has been around for at least 30 years by now (disclosure: figure out of the air, not researched) still hasn't developed much of a visual language. It's almost impossible to know when you can drag and drop things, and the only way to learn is to start trying by dragging on random UI elements. Of course, knowing what happens once you drop them on something that cares is just as impossible as knowing what you can drag in the first place. Sorry if I sound pessimistic, I hope development and focus is better now, and of course touch screen devices are in front of a much wider audience which might prompt a more rapid development of some standards.