I am a big fan of mindmaps. I think that Mind Manager is a terrific product but since I really started using about 3 different computers on a regular basis with at least one of them being very locked down, I've also been using MINDOMO and have been very impressed.
I have also found that the single best source for tracking mindmapping developments is the Mind Mapping Software Weblog by Chuck Frey. A couple of items of note that have been languishing in my tabs for a while now include:
How a 'dashboard' map supercharged the productivity of a team of project leaders: I love using mindmaps as front-ends to data.
Exploratree offers visual thinking guides: I've been tinkering with this now and think I really need to have task or something and try to use this to find out how really useful I think it is...looks pretty though.
Review: iMindMap 2.0 delivers an organic visual mapping experience, plus many business features: Chuck gave this product 5 stars and I do need to download and try the free trial on one of my dev boxes not only because of that rating but because the guy behind it Tony Buzan is a central figure in the popularization of this process. The site loudly hails Buzan as the "inventor" of mindmapping but I think that is probably as accurate as saying that Gagne, Bloom or Kirkpatrick is the 'inventor' of learning.
Mindmapping widget: from MindMeister comes this little widget that allows you to insert that great idea that just popped into your head, into your favorite mindmap via a desktop widget...I love the integration...