A company called Cirilab Inc., which specializes in developing software that can analyze unstructured text documents and can extract its major themes, has added the capability to export this data to a MindManager map. This page shows what a document synopsis looks like after it has been analyzed by the firm's "thematic extractor." Users can then export the visual outline (on the left side of the screen) to a MindManager map (pictured here) for further analysis. Cirilab is now seeking feedback on this new capability, which you can provide in the Mindjet discussion forums.
I presume that this would provide the same benefits as visual mapping does compared to a hierarchical outline -- increased clarity, and an improved ability to see connections between related topics.