There have always been two major concerns about cloud services in general, and cloud storage (Dropbox, Megaupload, SkyDrive, iCloud, and so on). The first is privacy: When you upload data to a third party, there’s always the risk that they can look at the contents of your files. Some cloud providers securely encrypt data, but many don’t. The second issue is data security and integrity: Does the third party keep a tight ship against hackers? What happens if a hard drive fails? What protections have the cloud provider put in place to mitigate against natural disasters, bankruptcy, or being shut down by the Feds?