We are running a Thought Leaders in Big Data series on the One Million by One Million blog. Bill Simmons of DataXu, John Plavan of Earthrisk, Derek Rodner of Agilence, Omer Artun of AgilOne, Raj De Dutta of BloomReach, Roman Stanek of GoodData would all be on my list of interviews to study to get a feel for use cases and functional areas. Just as an overview, you will see Marketing/Customer Analytics show up a lot.
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