This document summarizes a research paper that proposes a personalized hybrid recommendation system for e-commerce applications that can support massive datasets. The system uses clustering algorithms to build a user preference tree to model user interests. It then uses map-reduce on Hadoop to accelerate the recommendation algorithm using user and product similarity matrices in order to provide recommendations to users in an online mode quickly despite large, unstructured data. The performance of the map-reduce based system is analyzed and shown to have advantages over traditional centralized methods for large datasets.