There's an inherent promise in the idea that 'big data' will help us unlock various mysteries, solve all types of problems, and see or understand things from new perspectives. At a meeting I was at last week on 'Big Data in organisation design, development and workforce planning' this seemed to be the line we were taking.
By 'big data' I think we meant the vast amounts of structured and unstructured information amenable to being captured and coded into a computer where it is stored, manipulated and analysed through skills of data scientists who have expertise in machine learning, computational analysis, maths and statistics. But don't worry if you aren't sure what 'big data' is – take a look at an article that offers the varied definitions from 40 big data scientists.
For organisation design work using 'big data' and data visualisation is useful for developing scenarios and models, costing changes, assessing impacts of various changes that could be made and so on (See Rupert Morrison's book Data Driven Organisation Design for more on this.)