1. A system for providing sentiment analysis comprising: a data store comprising a plurality of content items and a plurality of labels, wherein the plurality of content items comprises a first content item and wherein the plurality labels comprises a first label; one or more processors configured to execute computer program modules, the computer program modules comprising: a sentiment analysis module, configured to analyze the plurality of content items, identify one or more portions of the first content item to be labeled with the first label, and assign a sentiment score to the one or more labeled portions; an interface module, configured to define a graphical user interface, the graphical user interface being configured to display the first content item, the graphical user interface being further configured to receive an entry and/or selection of inputs that label a portion of the first content item and provide a sentiment for the labeled portion; a content management module configured to, responsive to the user providing the sentiment for the labeled portion, update the data store to include the received label and further configured to instruct the sentiment analysis module to re-analyze the plurality of content items to update the sentiment score and to instruct the interface module to update the graphical user interface with the updated sentiment score, wherein the re-analyzing comprises searching all content items in the data store, identifying content items containing the received label, and recalculating the sentiment score for the at least one content item; a weighting module configured to assign a weight to the first label proportional to the frequency of the first label such that when the sentiment analysis module re-analyzes the plurality of content items, the sentiment score for the first content item is based in part on the weight, wherein the sentiment score varies dependent on a frequency of the first label.
2. The system of claim 1 wherein the entry and/or selection of inputs that label a portion of the content item for sentiment comprises an entry and/or selection of inputs that modify or delete an existing label or create a new label.