1. A method of producing a visual text summarization, the method comprising the steps of: extracting a plurality of topics from a collection of text documents, wherein each of the topics comprises a plurality of topic keywords; determining an importance ranking for each of the topics; determining an importance ranking for each of the topic keywords of a topic; displaying a graph having a plurality of stacked layers representing a group of topics selected from the plurality of topics based on the importance ranking of the topics; and displaying at least one keyword cloud within each layer of the graph, wherein the at least one keyword cloud is a group of topic keywords selected from the extracted topic keywords based on the importance ranking of the extracted topic keywords.