As as my personal history goes (all the way back to the Apple II), the entire category of "thinking tools" for computers originated with Dave Winer's ThinkTank outline processor and it's marvelous successor MORE. I use OmniOutliner on the Mac, and while it has features that ThinkTank and More never did, it just doesn't feel as natural as MORE. Then again, you're reading a guy who has over 20 years of Emacs muscle memory jammed in there too. Good as outlines are (and they are very good), sometimes you need something different. I've found that drawing a mind map is a good way to help me split out issues when I don't have a clear conceptual picture of what's going on. The big problem with mind maps is that they are hard to draw and maintain, especially when you are splitting nodes and moving them around. It's a total loss on paper -- it's precisely the thing that computers are good for. For a while I was using FreeMind, which is open source, but the interface left a lot to be desired.

Yesterday, MindJet launched the Macintosh version of their MindManager application for mind mapping. I've been using it as a beta tester for several months (Disclosure: I got a free copy of MindManager as a result), and I've been putting it to work generating maps of various kinds. I'm very happy with it -- the interface is reasonable, and I now have no qualms about creating a mind map if I think it would be remotely helpful for a problem that I am looking at. There is file compatibility with the Windows version of MindManager - I verified this by opening some maps that were created at Seattle Mind Camp 2.0. If you're looking for a mind mapping program, and you are picky about the interface, I think that you should download the free trial of MindManager for Mac and see for yourself.