1. A graph storage and processing system, comprising: a scalable, distributed, fault-tolerant, in-memory graph storage device for storing base graph data representative of at least one graph; a real-time, in memory graph storage device for storing update graph data with respect to a time threshold responsive to receiving the update graph data representative of a real-time update to the at least one graph, wherein the base graph data and any received update graph data form a complete graph structure of the at least one graph; a glue device for publishing any received update graph data as one or more live graph update feeds for use by one or more applications; an in-memory graph sampler for generating one or more sampled portions of the at least one graph by sampling the base graph data and for storing the one or more sampled portions; a query manager for providing a query interface between the one or more applications and the system; and a graph computer for processing the one or more sampled portions using batch-type computations to generate approximate results for the graph-based query, responsive to the query manager receiving a graph-based query from at least one of the one or more applications, wherein the glue device merges at least one of the one or more base sampled portions with any published update graph data from the one or more live graph update feeds.