A great mantra for software development that I paraphrased from the quote below from Joshua Schacter! Read the whole thing to learn more about tagging from Alex!
In the rush to design those tools, software developers would do well to heed Schachter's own approach to creating and extending the tagging functionality of del.icio.us itself. "I prefer to do stuff and see how people react and what people use and what they ignore," Schacter says. "Pay attention to how and what they do and make it so that they can do it."