The Mind Map Watch blog mines the internet - blogs and twitter reports - for articles released on mindmapping. The site has a regular Twitter update of these articles, plus a good list of MindMapping applications and software for creating mindmaps.
XMind is opensource mindmapping software, with a Pro version also. There are drilldown, workgroup and multiple sheet functions and the audio notes make this appealing for collobarative mindmaps.
Mindjet MindManager Pro - commercial software for mindmapping, with online collobaration, integration with MS Office, PDF outputs, Gantt Chart integration, a web side, and copious features, templates etc.
Originally for educational and classroom use, the Inspiration diagramming software is available for parents and private use also. Mindmap and turn into outlines etc. Commercial, now with a web side also.
A web app for mind mapping which requires no browser plug-ins , can share, export and publish your mind maps from the app and all is free and unlimited