Couldn’t agree more, Rafe on Labels versus folders, labels win. I have fallen in love with del.icio.us labels and started experimenting with them in Thunderbird, dumbing everything into one folder with lots of labeling.
Now if I could just do the same with my home direcory or My Documents. And if MovableType made it easier to label/categorize. Well Thunderbird needs more than 5 label options.