5. The system of claim 4 , wherein the folksonomy is derived from the groupings of tags for the documents by filtering the tags of the different groups to tags for which at least a threshold weight has been established.
4. A taxonomy generation data processing system configured for generating a document taxonomy based upon tag data in groupings of tags, the system comprising: a host computer with at least one processor and memory; a tagging system executing in the memory of the host computer; tag grouping module coupled to the tagging system, the tag grouping module comprising program code enabled to group individual tags into different groupings of tags for different corresponding documents and establish weights for the tags in the groups, the tags comprising meta-information provided by users to annotate bookmarks associated with the documents; and, taxonomy generation logic executing in the memory of the host computer, the logic comprising program code enabled to: derive a folksonomy from the groups of tags for the documents, infer parent-child relationships amongst the groupings of tags based on sorting the tags for each document by the weights; organize the folksonomy into a hierarchy of nodes based on the inferred parent-child relationships, each of the nodes being associated with a different subject in the folksonomy; and publish the hierarchy of nodes as a taxonomy for the documents to provide a top-down view of the documents.