1. A system for analysis of an opinion expressed in documents with regard to a particular topic, comprising: a data processing system including an opinion analysis module; a specification unit specifying at least one source of documents, and a topic of interest; a document retrieving unit operationally coupled to said specification unit and retrieving at least one document d on said topic of interest from said at least one source of documents for entrance into said opinion analysis module; said opinion analysis module having an opinion intensity scoring unit computing, at least on a substantially continuous numerical scale, an intensity of an opinion expressed in said at least one document on said topic of interest; and an opinion intensity representation unit outputting said computed opinion intensity in a multi-dimensional format.