US Patent 7596587 Multi-tiered storage

Methods and apparatus are described for storing a plurality of objects in a plurality of storage options. An importance index is generated for each of the plurality of objects with reference to importance data associated with each object. At least a portion of the importance data represents relevance of the associated object relative to a population of users interacting with the plurality of objects. Each of the objects is stored in a selected one of the storage options with reference to the corresponding importance index and a hierarchy of the storage options. The hierarchy of storage options represents at least partial ordering of the storage options with reference to economic costs and efficiency of retrieval.