This service would mostly be used by us who are wary about trusting Google/Microsoft/Dropbox and the judgement of their automated decision systems with our life . Yesterday there was a HN story about a guy who got kicked off Google Docs because an automated program was trolling/mining through their users files and its judgement was not to be questioned by mere mortals.
What if I put a picture of me and my kid playing in the swimming pool -- what is to prevent Dropbox/Google/Skydrive from tagging it as offensive and setting an overzealous DA or social-worker upon my family ? People have been arrested/detained at border crossings for perfectly innocuous pictures like these.
Therefore if you think privacy is only important for people stealing stuff, your are being naive.