From a business perspective, there is huge difference between plain polarity and topic-based sentiment analysis (also known as aspect-based sentiment analysis)
Quite often, documents express opinions, like web reviews or open-ended questions in market surveys. And most of the times documents don’t just represent a single point of view, a single opinion. Documents typically consist of multiple opinions representing several closely related but nuanced positions. By reducing a whole document to a single opinion score, many sentiment analysis services hide the best insights, the useful ones, and prevent clients from drilling down to extract the useful information.
Press release from Bitext:
The International Conference on Knowledge Capture (K-CAP) is a major venue for discussing the latest scientific results and innovation around diverse areas of knowledge capturing, including text mining, knowledge representation, knowledge acquisition, intelligent user interfaces and so on.
Press release from Tuitele and Bitext: