Did you use it with other people? While it can work on an individual level (i.e. where you are just making boards for yourself), that isn't really what it was designed for. I wouldn't put it in the same group of tools as personal productivity software. While you can use it for yourself, it really shines when you have a group of people trying to collaborate and share information.

It's especially useful for viewers (i.e. not people writing things in Trello, but people watching others update info and tracking the progress of something).