> How do you personally use mindmaps?
Depends which mapping program you use, but I think what you're probably missing is that in many mindmap programs, each 'bubble' can have attributes like due date, completion state, notes, task allocation, url links, document links, etc.
Some programs have an 'Outline view' that basically produces an editable to-do list when you toggle between graphical map and the outline list view. Some also have a static Gantt chart view (or even full Gantt charts with dragable timelines). Some can import/export Outlook task lists, and allow you to send tasks as emails.
So they can be quite powerful. If you've got several projects on the go, dozens of future ideas that you want to record and develop, if you frequently brainstorm stuff, and use GTD lists, then a mind map program might help you keep all that in one place.
The catch is that the free ones are fairly basic, and only tokenistically delve into some of the project management features mentioned above.