Note: As of 15-01-2014, this module appears to no longer be supported. If you are interested in taking this module over, please reply to the issue.
Vocabulary Index provides an easy way to create a taxonomy browser / directory index. You can choose for which vocabularies to create pages or blocks where the terms within that vocabulary are listed. With just a few clicks you're done. Listing is possible in different kind of views depending on your needs:
Views is the Swiss pocket knife for creating your own 'lists' of taxonomy data (and users, nodes, comments, etc.), but it cannot do what Vocabulary Index does. If you want to browse through a vocabulary's hierarchy, view its terms as a nested tree or browse terms by letter, then Vocabulary Index is the right tool for the job. If you want plain lists with lots of filters, custom sorting and limits, for instance, then you should use Views.