Calling them mind maps recalls why they failed, when they are really digraphs, taxonomies, and basic ontologies.

Having worked with these for a while, some people actually think their job is to be the stewards and gatekeepers of knowledge that can in fact be easily encoded into a taxonomy and ontology to make it scale.

I love these, and every tool like this is fundamentally subversive. Just don't be surprised when someone tries to discredit it.