I have been using labels for a long time but I think categories is also a must. It helps identify posts with the same context. One may argue that labels are supposed to do the same thing, put all posts with a context in the same place. But, the simple answer is that (at least) I use labels frivolously and I create labels
for fucks sake at the drop of the hat. With categories, I plan to be more organized and serious. Like this post for example. The labels could be personal, blogging, wordpress, blogger, thoughts etc. But if I was to put category to this one, I would say Blogging. I would use the plain old hashtag. So some categories that I have been able to think are #poker, #horrorStoriesFromWork, #attemptsAtFiction.
And no, I am not putting any categories on this post. May be I can put this post under #notifications? May be not!