You can create a good machine learning model for analyzing moods using Amazon ML.
Here is a link to a github project that does just that: https://github.com/awslabs/machine-learning-samples/tree/master/social-media
Since Amazon ML supports supervised learning, as well as text as an input attribute, you need to get sample data that has been tagged and build a model with it.
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, Kaggle : https://www.kaggle.com/c/sentiment-analysis-on-movie-reviews. Amazon ML .
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