Seems to be one of those HN posts with a lot of negativity and little constructive criticism.
I on the other hand immediately see a large niche market...lawyers/law firms. For example, here in Florida the Bar issued an ethics advisory opinion that deters lawyers from using cloud services altogether. The opinion calls out some cloud services by name, and specifically "noted a flurry of concern recently over Dropbox".
If you are interested in talking about the legal market send me a note.