Dropbox is cool. They identified a huge problem with information sharing, built a large scale cloud service that can be consumed from all of your devices, inc. tablets/smartphones, focussed heavily on ease of use & let the viral word-of-mouth market that comes with uber-coolness get to work. Their success comes from the simplicity. All your data available on all your devices without any management requirements/complexities. And herein lies the problem they created. All those management requirements/complexities are usually put in place as part of an organisations security strategy. Dropbox enabled data storage consumers to bypass IT Security for the sake of productivity.