Tagadelic views require you to specify one taxonomy field (e.g. Taxonomy: All Terms) in order to work. If you don't, you receive the following error message:
The Tagadelic View requires one vocabulary field.
This is confusing since the only relevant fields are listed as 'Taxonomy' fields.
This patch changes the error message to say:
The Tagadelic View requires one taxonomy field.
Small change, but one that would have saved me a lot of confusion.