8. The computer program product of claim 7 , wherein the computer readable program code for deriving a folksonomy from the groupings of tags for the documents, comprises computer readable program code for filtering the tags of the different groupings to tags for which at least a threshold weight has been established.
7. A computer program product for generating a document taxonomy based upon tag data in groupings of tags, the computer program product comprising: a computer readable hardware storage medium having computer readable program code embodied therewith, the computer readable program code comprising: computer readable program code for retrieving into memory of a host computer different groupings of tags for correspondingly different documents providing a bottom-up view of the documents, the tags comprising meta-information provided by users to annotate bookmarks associated with the documents; computer readable program code for deriving a folksonomy from the groupings of tags for the documents; computer readable program code for establishing weights for the tags in the groups; computer readable program code for inferring parent-child relationships amongst the groupings of tags based on sorting the tags for each document by the weights; computer readable program code for organizing 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, computer readable program code for publishing the hierarchy of nodes as a taxonomy for the documents to provide a top-down view of the documents.