Cloud computing has attracted a great deal of attention in both academia and industry. We envision the provisioning of differentiated services as being one of the key components to the success of cloud computing. Unfortunately, this issue has not been fully addressed in the past. Realizing that different users might have different requirements regarding availability, reliability, durability, response time and so on, we conjecture that providing flexible replication mechanism is the right approach to service differentiation. In this paper, we propose Differentiated Replication (DiR),which allows users to choose different replication strategies by considering both the user requirements and system capability. We implemented a system that offers four differentiated storage services with DiR. The experimental results show that this service actually provides different availabilities and execution times for different service types with the same request traces, failure traces, and workload. In addition, we also show that in comparison to the regular uniform replication, DiR can further improve resource utilization, which will in turn provide a better user experience with regards to cloud computing