]> 2010-05-11T00:00:00-05:00 The tools provided by statistical natural language processing and machine learning, along with exciting new scalable approaches to working with Big Data, make it possible to begin the work of extracting sentiment from the Web. We will discuss some of the challenges and approaches in doing this work. In particular, we will describe work we have done in annotating sentiment in blogs at the sentence and clausal level; in classifying subjectivity at the sentence level; and in identifying the targets, or topics, of sentiment at the clausal level. ]]> 4033552