I’d also like to hear about any research that focuses on how to allow / prompt users to change layout, attribute (size,color, transparency) assignment to match their primary question. Building different ways to represent data into an application is a certain level of difficulty. Making user interfaces that allow non-data-visualization specialists to pick the right options for their questions seems like a much harder problem, and one on which I’d like to hear more about in terms of successes, failures, and experimental studies.